diff --git a/installer/test/mix_helper.exs b/installer/test/mix_helper.exs
index 1addd2ec1f..baa047b732 100644
--- a/installer/test/mix_helper.exs
+++ b/installer/test/mix_helper.exs
@@ -28,7 +28,6 @@ defmodule MixHelper do
   end
 
   def in_tmp_project(which, function) do
-    conf_before = Application.get_env(:phoenix, :generators) || []
     base = Path.join([tmp_path(), random_string(10)])
     path = Path.join([base, to_string(which)])
 
@@ -38,24 +37,14 @@ defmodule MixHelper do
 
       File.cd!(path, fn ->
         File.touch!("mix.exs")
-
-        File.write!(".formatter.exs", """
-        [
-          import_deps: [:phoenix, :ecto, :ecto_sql],
-          inputs: ["*.exs"]
-        ]
-        """)
-
-        function.()
+        with_generator_env([format_extensions: []], function)
       end)
     after
       File.rm_rf!(base)
-      Application.put_env(:phoenix, :generators, conf_before)
     end
   end
 
   def in_tmp_umbrella_project(which, function) do
-    conf_before = Application.get_env(:phoenix, :generators) || []
     base = Path.join([tmp_path(), random_string(10)])
     path = Path.join([base, to_string(which)])
 
@@ -72,9 +61,10 @@ defmodule MixHelper do
         File.write!(Path.join(config_path, file), "import Config\n")
       end
 
-      File.cd!(apps_path, function)
+      File.cd!(apps_path, fn ->
+        with_generator_env([format_extensions: []], function)
+      end)
     after
-      Application.put_env(:phoenix, :generators, conf_before)
       File.rm_rf!(base)
     end
   end
@@ -131,15 +121,15 @@ defmodule MixHelper do
   end
 
   def with_generator_env(app_name \\ :phoenix, new_env, fun) do
-    config_before = Application.fetch_env(app_name, :generators)
-    Application.put_env(app_name, :generators, new_env)
+    config_before = Application.get_env(app_name, :generators)
+    Application.put_env(app_name, :generators, Keyword.merge(config_before || [], new_env))
 
     try do
       fun.()
     after
       case config_before do
-        {:ok, config} -> Application.put_env(app_name, :generators, config)
-        :error -> Application.delete_env(app_name, :generators)
+        nil -> Application.delete_env(app_name, :generators)
+        config -> Application.put_env(app_name, :generators, config)
       end
     end
   end
diff --git a/integration_test/test/code_generation/app_with_defaults_test.exs b/integration_test/test/code_generation/app_with_defaults_test.exs
index 57d069f794..cf8dd08605 100644
--- a/integration_test/test/code_generation/app_with_defaults_test.exs
+++ b/integration_test/test/code_generation/app_with_defaults_test.exs
@@ -27,7 +27,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithDefaultsTest do
       with_installer_tmp("app_with_defaults", fn tmp_dir ->
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "phx_blog")
 
-        mix_run!(~w(phx.gen.html Blog Post posts title:unique body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.html Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/phx_blog_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -74,7 +84,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithDefaultsTest do
       with_installer_tmp("app_with_defaults", fn tmp_dir ->
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "phx_blog")
 
-        mix_run!(~w(phx.gen.json Blog Post posts title:unique body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.json Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/phx_blog_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -121,7 +141,18 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithDefaultsTest do
       with_installer_tmp("app_with_defaults", fn tmp_dir ->
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "phx_blog", ["--live"])
 
-        mix_run!(~w(phx.gen.live Blog Post posts title:unique body:string p:boolean s:enum:a:b:c), app_root_path)
+        mix_run!(
+          ~w(phx.gen.live Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            public:boolean
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/phx_blog_web/router.ex"), fn file ->
           inject_before_final_end(file, """
diff --git a/integration_test/test/code_generation/app_with_mssql_adapter_test.exs b/integration_test/test/code_generation/app_with_mssql_adapter_test.exs
index 96ca203de2..0b9903b748 100644
--- a/integration_test/test/code_generation/app_with_mssql_adapter_test.exs
+++ b/integration_test/test/code_generation/app_with_mssql_adapter_test.exs
@@ -87,7 +87,14 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMSSQLAdapterTest do
       with_installer_tmp("new with defaults", fn tmp_dir ->
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "phx_blog", ["--database", "mssql", "--live"])
 
-        mix_run!(~w(phx.gen.html Accounts Group groups name), app_root_path)
+        mix_run!(
+          ~w(phx.gen.html Accounts Group groups
+            name
+            details
+            other_very_important_attribute
+            one_more_attribute_with_long_name),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/phx_blog_web/router.ex"), fn file ->
           inject_before_final_end(file, """
diff --git a/integration_test/test/code_generation/app_with_mysql_adapter_test.exs b/integration_test/test/code_generation/app_with_mysql_adapter_test.exs
index 0886d421f9..936efe9262 100644
--- a/integration_test/test/code_generation/app_with_mysql_adapter_test.exs
+++ b/integration_test/test/code_generation/app_with_mysql_adapter_test.exs
@@ -8,7 +8,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_mysql_app", ["--database", "mysql"])
 
-        mix_run!(~w(phx.gen.html Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.html Blog Post posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_mysql_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -21,6 +31,9 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
           """)
         end)
 
+        # TODO: Uncomment when fix unformatted code from `phx.new` generator.
+        # assert_no_compilation_warnings(app_root_path)
+        # assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
@@ -34,7 +47,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_mysql_app", ["--database", "mysql"])
 
-        mix_run!(~w(phx.gen.json Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.json Blog Post posts posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_mysql_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -47,6 +70,9 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
           """)
         end)
 
+        # TODO: Uncomment when fix unformatted code from `phx.new` generator.
+        # assert_no_compilation_warnings(app_root_path)
+        # assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
@@ -60,7 +86,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_mysql_app", ["--database", "mysql", "--live"])
 
-        mix_run!(~w(phx.gen.live Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.live Blog Post posts posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_mysql_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -76,6 +112,9 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithMySqlAdapterTest do
           """)
         end)
 
+        # TODO: Uncomment when fix unformatted code from `phx.new` generator.
+        # assert_no_compilation_warnings(app_root_path)
+        # assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
diff --git a/integration_test/test/code_generation/app_with_sqlite3_adapter.exs b/integration_test/test/code_generation/app_with_sqlite3_adapter.exs
index 4576a6cfc0..b0871603b1 100644
--- a/integration_test/test/code_generation/app_with_sqlite3_adapter.exs
+++ b/integration_test/test/code_generation/app_with_sqlite3_adapter.exs
@@ -8,7 +8,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_sqlite3_app", ["--database", "sqlite3"])
 
-        mix_run!(~w(phx.gen.html Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.html Blog Post posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_sqlite3_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -21,6 +31,8 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
           """)
         end)
 
+        assert_no_compilation_warnings(app_root_path)
+        assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
@@ -34,7 +46,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_sqlite3_app", ["--database", "sqlite3"])
 
-        mix_run!(~w(phx.gen.json Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.json Blog Post posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_sqlite3_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -47,6 +69,8 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
           """)
         end)
 
+        assert_no_compilation_warnings(app_root_path)
+        assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
@@ -60,7 +84,17 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
         {app_root_path, _} =
           generate_phoenix_app(tmp_dir, "default_sqlite3_app", ["--database", "sqlite3", "--live"])
 
-        mix_run!(~w(phx.gen.live Blog Post posts title body:string status:enum:unpublished:published:deleted), app_root_path)
+        mix_run!(
+          ~w(phx.gen.live Blog Post posts
+            title
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          app_root_path
+        )
 
         modify_file(Path.join(app_root_path, "lib/default_sqlite3_app_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -76,6 +110,8 @@ defmodule Phoenix.Integration.CodeGeneration.AppWithSQLite3AdapterTest do
           """)
         end)
 
+        assert_no_compilation_warnings(app_root_path)
+        assert_passes_formatter_check(app_root_path)
         drop_test_database(app_root_path)
         assert_tests_pass(app_root_path)
       end)
diff --git a/integration_test/test/code_generation/umbrella_app_with_defaults_test.exs b/integration_test/test/code_generation/umbrella_app_with_defaults_test.exs
index 9dc71ba64d..0fdd0b09a1 100644
--- a/integration_test/test/code_generation/umbrella_app_with_defaults_test.exs
+++ b/integration_test/test/code_generation/umbrella_app_with_defaults_test.exs
@@ -29,7 +29,17 @@ defmodule Phoenix.Integration.CodeGeneration.UmbrellaAppWithDefaultsTest do
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "rainy_day", ["--umbrella"])
         web_root_path = Path.join(app_root_path, "apps/rainy_day_web")
 
-        mix_run!(~w(phx.gen.html Blog Post posts title:unique body:string status:enum:unpublished:published:deleted), web_root_path)
+        mix_run!(
+          ~w(phx.gen.html Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          web_root_path
+        )
 
         modify_file(Path.join(web_root_path, "lib/rainy_day_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -78,7 +88,17 @@ defmodule Phoenix.Integration.CodeGeneration.UmbrellaAppWithDefaultsTest do
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "rainy_day", ["--umbrella"])
         web_root_path = Path.join(app_root_path, "apps/rainy_day_web")
 
-        mix_run!(~w(phx.gen.json Blog Post posts title:unique body:string status:enum:unpublished:published:deleted), web_root_path)
+        mix_run!(
+          ~w(phx.gen.json Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          web_root_path
+        )
 
         modify_file(Path.join(web_root_path, "lib/rainy_day_web/router.ex"), fn file ->
           inject_before_final_end(file, """
@@ -127,7 +147,17 @@ defmodule Phoenix.Integration.CodeGeneration.UmbrellaAppWithDefaultsTest do
         {app_root_path, _} = generate_phoenix_app(tmp_dir, "rainy_day", ["--umbrella", "--live"])
         web_root_path = Path.join(app_root_path, "apps/rainy_day_web")
 
-        mix_run!(~w(phx.gen.live Blog Post posts title:unique body:string status:enum:unpublished:published:deleted), web_root_path)
+        mix_run!(
+          ~w(phx.gen.live Blog Post posts
+            title:unique
+            body:string
+            preface
+            author_name
+            author_email
+            other_very_important_attribute
+            status:enum:unpublished:published:deleted),
+          web_root_path
+        )
 
         modify_file(Path.join(web_root_path, "lib/rainy_day_web/router.ex"), fn file ->
           inject_before_final_end(file, """
diff --git a/lib/mix/phoenix.ex b/lib/mix/phoenix.ex
index 78181df0b1..24b5f1d793 100644
--- a/lib/mix/phoenix.ex
+++ b/lib/mix/phoenix.ex
@@ -65,6 +65,43 @@ defmodule Mix.Phoenix do
   defp to_app_source(app, source_dir) when is_atom(app),
     do: Application.app_dir(app, source_dir)
 
+  @default_format_extensions [".ex", ".exs", ".heex"]
+  @doc """
+  Conditionally run `mix format` for generated files.
+  By default files with extensions `#{inspect(@default_format_extensions)}` are formatted.
+  It can be adjusted with generators config `format_extensions`, and turned off with value `[]`.
+  If no files pass condition, formatting is not performed.
+  """
+  def maybe_format(files) when is_list(files) do
+    format_extensions =
+      Application.get_env(otp_app(), :generators, [])
+      |> Keyword.get(:format_extensions, @default_format_extensions)
+
+    files = Enum.filter(files, &String.ends_with?(&1, format_extensions))
+    if files != [], do: Mix.Task.run("format", files)
+  end
+
+  @doc """
+  Format docs with override instruction.
+  """
+  def override_format_instruction do
+    """
+
+    Files with generated content (new and modified) are formatted with `mix format`.
+
+    By default files with extensions `#{inspect(@default_format_extensions)}` are formatted.
+    List of extensions can be changed via generators config:
+
+        config :your_app, :generators,
+          format_extensions: [".ex", ".exs"]
+
+    Formatting can be turned off by setting empty list:
+
+        config :your_app, :generators,
+          format_extensions: []
+    """
+  end
+
   @doc """
   Inflects path, scope, alias and more from the given name.
 
diff --git a/lib/mix/tasks/phx.gen.context.ex b/lib/mix/tasks/phx.gen.context.ex
index 1dfad60e39..6516ab8ff5 100644
--- a/lib/mix/tasks/phx.gen.context.ex
+++ b/lib/mix/tasks/phx.gen.context.ex
@@ -72,6 +72,10 @@ defmodule Mix.Tasks.Phx.Gen.Context do
   You can skip this prompt and automatically merge the new schema access functions and tests into the
   existing context using `--merge-with-existing-context`. To prevent changes to
   the existing context and exit the generator, use `--no-merge-with-existing-context`.
+
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
 
   use Mix.Task
@@ -112,6 +116,7 @@ defmodule Mix.Tasks.Phx.Gen.Context do
 
     context
     |> copy_new_files(paths, binding)
+    |> format_files()
     |> print_shell_instructions()
   end
 
@@ -149,17 +154,18 @@ defmodule Mix.Tasks.Phx.Gen.Context do
   end
 
   @doc false
+  def files_to_be_generated(%Context{generate?: false}), do: []
+
   def files_to_be_generated(%Context{schema: schema}) do
-    if schema.generate? do
-      Gen.Schema.files_to_be_generated(schema)
-    else
-      []
-    end
+    Gen.Schema.files_to_be_generated(schema)
   end
 
   @doc false
+  def copy_new_files(%Context{generate?: false} = context, _, _), do: context
+
   def copy_new_files(%Context{schema: schema} = context, paths, binding) do
-    if schema.generate?, do: Gen.Schema.copy_new_files(schema, paths, binding)
+    Gen.Schema.copy_new_files(schema, paths, binding)
+
     inject_schema_access(context, paths, binding)
     inject_tests(context, paths, binding)
     inject_test_fixture(context, paths, binding)
@@ -293,13 +299,24 @@ defmodule Mix.Tasks.Phx.Gen.Context do
     end
   end
 
+  defp format_files(%Context{} = context) do
+    files_to_format(context) |> Mix.Phoenix.maybe_format()
+    context
+  end
+
+  @doc false
+  def files_to_format(%Context{generate?: false}), do: []
+
+  def files_to_format(%Context{schema: schema} = context) do
+    [context.file, context.test_file, context.test_fixtures_file] ++
+      Gen.Schema.files_to_format(schema)
+  end
+
   @doc false
+  def print_shell_instructions(%Context{generate?: false}), do: :ok
+
   def print_shell_instructions(%Context{schema: schema}) do
-    if schema.generate? do
-      Gen.Schema.print_shell_instructions(schema)
-    else
-      :ok
-    end
+    Gen.Schema.print_shell_instructions(schema)
   end
 
   defp schema_access_template(%Context{schema: schema}) do
diff --git a/lib/mix/tasks/phx.gen.embedded.ex b/lib/mix/tasks/phx.gen.embedded.ex
index 4e82eec674..edb9c644ce 100644
--- a/lib/mix/tasks/phx.gen.embedded.ex
+++ b/lib/mix/tasks/phx.gen.embedded.ex
@@ -28,7 +28,12 @@ defmodule Mix.Tasks.Phx.Gen.Embedded do
 
   #{for attr <- Mix.Phoenix.Schema.valid_types(), do: "  * `#{inspect attr}`\n"}
     * `:datetime` - An alias for `:naive_datetime`
+
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
+
   use Mix.Task
 
   alias Mix.Phoenix.Schema
@@ -47,13 +52,16 @@ defmodule Mix.Tasks.Phx.Gen.Embedded do
 
     prompt_for_conflicts(schema)
 
-    copy_new_files(schema, paths, schema: schema)
+    schema
+    |> copy_new_files(paths, schema: schema)
+    |> format_files()
   end
 
   @doc false
   def build(args) do
     {schema_opts, parsed, _} = OptionParser.parse(args, switches: @switches)
     [schema_name | attrs] = validate_args!(parsed)
+
     opts =
       schema_opts
       |> Keyword.put(:embedded, true)
@@ -72,6 +80,7 @@ defmodule Mix.Tasks.Phx.Gen.Embedded do
       raise_with_help "Expected the schema argument, #{inspect schema}, to be a valid module name"
     end
   end
+
   def validate_args!(_) do
     raise_with_help "Invalid arguments"
   end
@@ -96,16 +105,21 @@ defmodule Mix.Tasks.Phx.Gen.Embedded do
     |> Mix.Phoenix.prompt_for_conflicts()
   end
 
-  @doc false
-  def files_to_be_generated(%Schema{} = schema) do
+  defp files_to_be_generated(%Schema{} = schema) do
     [{:eex, "embedded_schema.ex", schema.file}]
   end
 
-  @doc false
-  def copy_new_files(%Schema{} = schema, paths, binding) do
+  defp copy_new_files(%Schema{} = schema, paths, binding) do
     files = files_to_be_generated(schema)
     Mix.Phoenix.copy_from(paths, "priv/templates/phx.gen.embedded", binding, files)
 
     schema
   end
+
+  defp format_files(%Schema{} = schema) do
+    files_to_format(schema) |> Mix.Phoenix.maybe_format()
+    schema
+  end
+
+  defp files_to_format(%Schema{} = schema), do: [schema.file]
 end
diff --git a/lib/mix/tasks/phx.gen.html.ex b/lib/mix/tasks/phx.gen.html.ex
index e9222dacc5..57410d1e24 100644
--- a/lib/mix/tasks/phx.gen.html.ex
+++ b/lib/mix/tasks/phx.gen.html.ex
@@ -88,7 +88,12 @@ defmodule Mix.Tasks.Phx.Gen.Html do
   You can also change the table name or configure the migrations to
   use binary ids for primary keys, see `mix phx.gen.schema` for more
   information.
+
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
+
   use Mix.Task
 
   alias Mix.Phoenix.{Context, Schema}
@@ -107,31 +112,24 @@ defmodule Mix.Tasks.Phx.Gen.Html do
     {context, schema} = Gen.Context.build(args)
     Gen.Context.prompt_for_code_injection(context)
 
-    binding = [context: context, schema: schema, inputs: inputs(schema)]
+    binding = [context: context, schema: schema]
     paths = Mix.Phoenix.generator_paths()
 
     prompt_for_conflicts(context)
 
     context
     |> copy_new_files(paths, binding)
+    |> format_files()
     |> print_shell_instructions()
   end
 
   defp prompt_for_conflicts(context) do
     context
     |> files_to_be_generated()
-    |> Kernel.++(context_files(context))
+    |> Kernel.++(Gen.Context.files_to_be_generated(context))
     |> Mix.Phoenix.prompt_for_conflicts()
   end
 
-  defp context_files(%Context{generate?: true} = context) do
-    Gen.Context.files_to_be_generated(context)
-  end
-
-  defp context_files(%Context{generate?: false}) do
-    []
-  end
-
   @doc false
   def files_to_be_generated(%Context{schema: schema, context_app: context_app}) do
     singular = schema.singular
@@ -157,12 +155,25 @@ defmodule Mix.Tasks.Phx.Gen.Html do
 
   @doc false
   def copy_new_files(%Context{} = context, paths, binding) do
+    Gen.Context.copy_new_files(context, paths, binding)
+
+    binding = Keyword.merge(binding, inputs: inputs(context.schema))
     files = files_to_be_generated(context)
     Mix.Phoenix.copy_from(paths, "priv/templates/phx.gen.html", binding, files)
-    if context.generate?, do: Gen.Context.copy_new_files(context, paths, binding)
+
     context
   end
 
+  defp format_files(%Context{} = context) do
+    files_to_format(context) |> Mix.Phoenix.maybe_format()
+    context
+  end
+
+  defp files_to_format(%Context{} = context) do
+    (files_to_be_generated(context) |> Enum.map(fn {_, _, file} -> file end)) ++
+      Gen.Context.files_to_format(context)
+  end
+
   @doc false
   def print_shell_instructions(%Context{schema: schema, context_app: ctx_app} = context) do
     if schema.web_namespace do
@@ -185,7 +196,7 @@ defmodule Mix.Tasks.Phx.Gen.Html do
       """)
     end
 
-    if context.generate?, do: Gen.Context.print_shell_instructions(context)
+    Gen.Context.print_shell_instructions(context)
   end
 
   @doc false
diff --git a/lib/mix/tasks/phx.gen.json.ex b/lib/mix/tasks/phx.gen.json.ex
index 97177b4935..a31fa32662 100644
--- a/lib/mix/tasks/phx.gen.json.ex
+++ b/lib/mix/tasks/phx.gen.json.ex
@@ -85,6 +85,10 @@ defmodule Mix.Tasks.Phx.Gen.Json do
   You can also change the table name or configure the migrations to
   use binary ids for primary keys, see `mix phx.gen.schema` for more
   information.
+
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
 
   use Mix.Task
@@ -116,24 +120,17 @@ defmodule Mix.Tasks.Phx.Gen.Json do
 
     context
     |> copy_new_files(paths, binding)
+    |> format_files()
     |> print_shell_instructions()
   end
 
   defp prompt_for_conflicts(context) do
     context
     |> files_to_be_generated()
-    |> Kernel.++(context_files(context))
+    |> Kernel.++(Gen.Context.files_to_be_generated(context))
     |> Mix.Phoenix.prompt_for_conflicts()
   end
 
-  defp context_files(%Context{generate?: true} = context) do
-    Gen.Context.files_to_be_generated(context)
-  end
-
-  defp context_files(%Context{generate?: false}) do
-    []
-  end
-
   @doc false
   def files_to_be_generated(%Context{schema: schema, context_app: context_app}) do
     singular = schema.singular
@@ -154,13 +151,24 @@ defmodule Mix.Tasks.Phx.Gen.Json do
 
   @doc false
   def copy_new_files(%Context{} = context, paths, binding) do
+    Gen.Context.copy_new_files(context, paths, binding)
+
     files = files_to_be_generated(context)
     Mix.Phoenix.copy_from(paths, "priv/templates/phx.gen.json", binding, files)
-    if context.generate?, do: Gen.Context.copy_new_files(context, paths, binding)
 
     context
   end
 
+  defp format_files(%Context{} = context) do
+    files_to_format(context) |> Mix.Phoenix.maybe_format()
+    context
+  end
+
+  defp files_to_format(%Context{} = context) do
+    (files_to_be_generated(context) |> Enum.map(fn {_, _, file} -> file end)) ++
+      Gen.Context.files_to_format(context)
+  end
+
   @doc false
   def print_shell_instructions(%Context{schema: schema, context_app: ctx_app} = context) do
     if schema.web_namespace do
@@ -183,6 +191,6 @@ defmodule Mix.Tasks.Phx.Gen.Json do
       """)
     end
 
-    if context.generate?, do: Gen.Context.print_shell_instructions(context)
+    Gen.Context.print_shell_instructions(context)
   end
 end
diff --git a/lib/mix/tasks/phx.gen.live.ex b/lib/mix/tasks/phx.gen.live.ex
index 3aa01cdd02..27ef798fd9 100644
--- a/lib/mix/tasks/phx.gen.live.ex
+++ b/lib/mix/tasks/phx.gen.live.ex
@@ -99,7 +99,12 @@ defmodule Mix.Tasks.Phx.Gen.Live do
   You can also change the table name or configure the migrations to
   use binary ids for primary keys, see `mix help phx.gen.schema` for more
   information.
+
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
+
   use Mix.Task
 
   alias Mix.Phoenix.{Context, Schema}
@@ -118,7 +123,7 @@ defmodule Mix.Tasks.Phx.Gen.Live do
     {context, schema} = Gen.Context.build(args)
     Gen.Context.prompt_for_code_injection(context)
 
-    binding = [context: context, schema: schema, inputs: inputs(schema)]
+    binding = [context: context, schema: schema]
     paths = Mix.Phoenix.generator_paths()
 
     prompt_for_conflicts(context)
@@ -126,24 +131,17 @@ defmodule Mix.Tasks.Phx.Gen.Live do
     context
     |> copy_new_files(binding, paths)
     |> maybe_inject_imports()
+    |> format_files()
     |> print_shell_instructions()
   end
 
   defp prompt_for_conflicts(context) do
     context
     |> files_to_be_generated()
-    |> Kernel.++(context_files(context))
+    |> Kernel.++(Gen.Context.files_to_be_generated(context))
     |> Mix.Phoenix.prompt_for_conflicts()
   end
 
-  defp context_files(%Context{generate?: true} = context) do
-    Gen.Context.files_to_be_generated(context)
-  end
-
-  defp context_files(%Context{generate?: false}) do
-    []
-  end
-
   defp files_to_be_generated(%Context{schema: schema, context_app: context_app}) do
     web_prefix = Mix.Phoenix.web_path(context_app)
     test_prefix = Mix.Phoenix.web_test_path(context_app)
@@ -163,18 +161,19 @@ defmodule Mix.Tasks.Phx.Gen.Live do
   end
 
   defp copy_new_files(%Context{} = context, binding, paths) do
-    files = files_to_be_generated(context)
+    Gen.Context.copy_new_files(context, paths, binding)
 
     binding =
       Keyword.merge(binding,
+        inputs: inputs(context.schema),
         assigns: %{
           web_namespace: inspect(context.web_module),
           gettext: true
         }
       )
 
+    files = files_to_be_generated(context)
     Mix.Phoenix.copy_from(paths, "priv/templates/phx.gen.live", binding, files)
-    if context.generate?, do: Gen.Context.copy_new_files(context, paths, binding)
 
     context
   end
@@ -224,6 +223,16 @@ defmodule Mix.Tasks.Phx.Gen.Live do
     end
   end
 
+  defp format_files(%Context{} = context) do
+    files_to_format(context) |> Mix.Phoenix.maybe_format()
+    context
+  end
+
+  defp files_to_format(%Context{} = context) do
+    (files_to_be_generated(context) |> Enum.map(fn {_, _, file} -> file end)) ++
+      Gen.Context.files_to_format(context)
+  end
+
   @doc false
   def print_shell_instructions(%Context{schema: schema, context_app: ctx_app} = context) do
     prefix = Module.concat(context.web_module, schema.web_namespace)
@@ -250,7 +259,7 @@ defmodule Mix.Tasks.Phx.Gen.Live do
       """)
     end
 
-    if context.generate?, do: Gen.Context.print_shell_instructions(context)
+    Gen.Context.print_shell_instructions(context)
     maybe_print_upgrade_info()
   end
 
diff --git a/lib/mix/tasks/phx.gen.schema.ex b/lib/mix/tasks/phx.gen.schema.ex
index 68f3c82ddf..35b03efd4a 100644
--- a/lib/mix/tasks/phx.gen.schema.ex
+++ b/lib/mix/tasks/phx.gen.schema.ex
@@ -107,7 +107,6 @@ defmodule Mix.Tasks.Phx.Gen.Schema do
 
       $ mix phx.gen.schema Blog.Post posts --migration-dir /path/to/directory
 
-
   ## prefix
 
   By default migrations and schemas are generated without a prefix.
@@ -147,7 +146,11 @@ defmodule Mix.Tasks.Phx.Gen.Schema do
   instead of a `NaiveDateTime`. This can also be set to `:utc_datetime_usec` for
   microsecond precision.
 
+  ## Format
+  #{Mix.Phoenix.override_format_instruction()}
+
   """
+
   use Mix.Task
 
   alias Mix.Phoenix.Schema
@@ -169,6 +172,7 @@ defmodule Mix.Tasks.Phx.Gen.Schema do
 
     schema
     |> copy_new_files(paths, schema: schema)
+    |> format_files()
     |> print_shell_instructions()
   end
 
@@ -206,40 +210,54 @@ defmodule Mix.Tasks.Phx.Gen.Schema do
   end
 
   @doc false
+  def files_to_be_generated(%Schema{generate?: false}), do: []
+
   def files_to_be_generated(%Schema{} = schema) do
     [{:eex, "schema.ex", schema.file}]
   end
 
   @doc false
-  def copy_new_files(%Schema{context_app: ctx_app, repo: repo, opts: opts} = schema, paths, binding) do
-    files = files_to_be_generated(schema)
+  def copy_new_files(%Schema{generate?: false} = schema, _, _), do: schema
+
+  def copy_new_files(%Schema{} = schema, paths, binding) do
+    migration_file =
+      if schema.migration?, do: [{:eex, "migration.exs", migration_path(schema)}], else: []
+
+    files = files_to_be_generated(schema) ++ migration_file
     Mix.Phoenix.copy_from(paths, "priv/templates/phx.gen.schema", binding, files)
 
-    if schema.migration? do
-      migration_dir =
-        cond do
-          migration_dir = opts[:migration_dir] ->
-            migration_dir
+    schema
+  end
 
-          opts[:repo] ->
-            repo_name = repo |> Module.split() |> List.last() |> Macro.underscore()
-            Mix.Phoenix.context_app_path(ctx_app, "priv/#{repo_name}/migrations/")
+  defp migration_path(%Schema{context_app: ctx_app, repo: repo, opts: opts, table: table}) do
+    migration_dir =
+      cond do
+        migration_dir = opts[:migration_dir] ->
+          migration_dir
 
-          true ->
-            Mix.Phoenix.context_app_path(ctx_app, "priv/repo/migrations/")
-        end
+        opts[:repo] ->
+          repo_name = repo |> Module.split() |> List.last() |> Macro.underscore()
+          Mix.Phoenix.context_app_path(ctx_app, "priv/#{repo_name}/migrations/")
 
-      migration_path = Path.join(migration_dir, "#{timestamp()}_create_#{schema.table}.exs")
+        true ->
+          Mix.Phoenix.context_app_path(ctx_app, "priv/repo/migrations/")
+      end
 
-      Mix.Phoenix.copy_from paths, "priv/templates/phx.gen.schema", binding, [
-        {:eex, "migration.exs", migration_path},
-      ]
-    end
+    Path.join(migration_dir, "#{timestamp()}_create_#{table}.exs")
+  end
 
+  defp format_files(%Schema{} = schema) do
+    files_to_format(schema) |> Mix.Phoenix.maybe_format()
     schema
   end
 
   @doc false
+  def files_to_format(%Schema{generate?: false}), do: []
+  def files_to_format(%Schema{} = schema), do: [schema.file, migration_path(schema)]
+
+  @doc false
+  def print_shell_instructions(%Schema{generate?: false}), do: :ok
+
   def print_shell_instructions(%Schema{} = schema) do
     if schema.migration? do
       Mix.shell().info """
@@ -262,6 +280,7 @@ defmodule Mix.Tasks.Phx.Gen.Schema do
         args
     end
   end
+
   def validate_args!(_, help) do
     help.raise_with_help "Invalid arguments"
   end
diff --git a/test/mix/tasks/phx.gen.html_test.exs b/test/mix/tasks/phx.gen.html_test.exs
index 450e0599b7..0b4c4e1ead 100644
--- a/test/mix/tasks/phx.gen.html_test.exs
+++ b/test/mix/tasks/phx.gen.html_test.exs
@@ -331,6 +331,7 @@ defmodule Mix.Tasks.Phx.Gen.HtmlTest do
   test "with a matching plural and singular term", config do
     in_tmp_project(config.test, fn ->
       Gen.Html.run(~w(Tracker Series series value:integer))
+
       assert_file("lib/phoenix_web/controllers/series_controller.ex", fn file ->
         assert file =~ "render(conn, :index, series_collection: series)"
       end)
@@ -399,58 +400,60 @@ defmodule Mix.Tasks.Phx.Gen.HtmlTest do
   describe "inside umbrella" do
     test "without context_app generators config uses web dir", config do
       in_tmp_umbrella_project(config.test, fn ->
-        Application.put_env(:phoenix, :generators, context_app: nil)
-        Gen.Html.run(~w(Accounts User users name:string))
+        with_generator_env([context_app: nil], fn ->
+          Gen.Html.run(~w(Accounts User users name:string))
 
-        assert_file("lib/phoenix/accounts.ex")
-        assert_file("lib/phoenix/accounts/user.ex")
+          assert_file("lib/phoenix/accounts.ex")
+          assert_file("lib/phoenix/accounts/user.ex")
 
-        assert_file("lib/phoenix_web/controllers/user_controller.ex", fn file ->
-          assert file =~ "defmodule PhoenixWeb.UserController"
-          assert file =~ "use PhoenixWeb, :controller"
-        end)
+          assert_file("lib/phoenix_web/controllers/user_controller.ex", fn file ->
+            assert file =~ "defmodule PhoenixWeb.UserController"
+            assert file =~ "use PhoenixWeb, :controller"
+          end)
 
-        assert_file("lib/phoenix_web/controllers/user_html.ex", fn file ->
-          assert file =~ "defmodule PhoenixWeb.UserHTML"
-        end)
+          assert_file("lib/phoenix_web/controllers/user_html.ex", fn file ->
+            assert file =~ "defmodule PhoenixWeb.UserHTML"
+          end)
 
-        assert_file("test/phoenix_web/controllers/user_controller_test.exs", fn file ->
-          assert file =~ "defmodule PhoenixWeb.UserControllerTest"
+          assert_file("test/phoenix_web/controllers/user_controller_test.exs", fn file ->
+            assert file =~ "defmodule PhoenixWeb.UserControllerTest"
+          end)
         end)
       end)
     end
 
     test "raises with false context_app", config do
       in_tmp_umbrella_project(config.test, fn ->
-        Application.put_env(:phoenix, :generators, context_app: false)
-
-        assert_raise Mix.Error, ~r/no context_app configured/, fn ->
-          Gen.Html.run(~w(Accounts User users name:string))
-        end
+        with_generator_env([context_app: false], fn ->
+          assert_raise Mix.Error, ~r/no context_app configured/, fn ->
+            Gen.Html.run(~w(Accounts User users name:string))
+          end
+        end)
       end)
     end
 
     test "with context_app generators config does not use web dir", config do
       in_tmp_umbrella_project(config.test, fn ->
         File.mkdir!("another_app")
-        Application.put_env(:phoenix, :generators, context_app: {:another_app, "another_app"})
 
-        Gen.Html.run(~w(Accounts User users name:string))
+        with_generator_env([context_app: {:another_app, "another_app"}], fn ->
+          Gen.Html.run(~w(Accounts User users name:string))
 
-        assert_file("another_app/lib/another_app/accounts.ex")
-        assert_file("another_app/lib/another_app/accounts/user.ex")
+          assert_file("another_app/lib/another_app/accounts.ex")
+          assert_file("another_app/lib/another_app/accounts/user.ex")
 
-        assert_file("lib/phoenix/controllers/user_controller.ex", fn file ->
-          assert file =~ "defmodule Phoenix.UserController"
-          assert file =~ "use Phoenix, :controller"
-        end)
+          assert_file("lib/phoenix/controllers/user_controller.ex", fn file ->
+            assert file =~ "defmodule Phoenix.UserController"
+            assert file =~ "use Phoenix, :controller"
+          end)
 
-        assert_file("lib/phoenix/controllers/user_html.ex", fn file ->
-          assert file =~ "defmodule Phoenix.UserHTML"
-        end)
+          assert_file("lib/phoenix/controllers/user_html.ex", fn file ->
+            assert file =~ "defmodule Phoenix.UserHTML"
+          end)
 
-        assert_file("test/phoenix/controllers/user_controller_test.exs", fn file ->
-          assert file =~ "defmodule Phoenix.UserControllerTest"
+          assert_file("test/phoenix/controllers/user_controller_test.exs", fn file ->
+            assert file =~ "defmodule Phoenix.UserControllerTest"
+          end)
         end)
       end)
     end