diff --git a/test/plugin/dayOfYear.d.test.ts b/test/plugin/dayOfYear.d.test.ts
new file mode 100644
index 000000000..85173c66e
--- /dev/null
+++ b/test/plugin/dayOfYear.d.test.ts
@@ -0,0 +1,6 @@
+import * as dayjs from 'dayjs'
+import * as dayOfYear from 'dayjs/plugin/dayOfYear'
+
+dayjs.extend(dayOfYear)
+
+dayjs('2015-01-01T00:00:00.000').dayOfYear() === 1
diff --git a/test/plugin/isSameOrAfter.d.test.ts b/test/plugin/isSameOrAfter.d.test.ts
new file mode 100644
index 000000000..b8f257cfd
--- /dev/null
+++ b/test/plugin/isSameOrAfter.d.test.ts
@@ -0,0 +1,6 @@
+import * as dayjs from 'dayjs'
+import * as isSameOrAfter from 'dayjs/plugin/isSameOrAfter'
+
+dayjs.extend(isSameOrAfter)
+
+dayjs('2010-10-20').isSameOrAfter('2010-10-19', 'year') === true
diff --git a/test/plugin/isSameOrBefore.d.test.ts b/test/plugin/isSameOrBefore.d.test.ts
new file mode 100644
index 000000000..5dcf966ee
--- /dev/null
+++ b/test/plugin/isSameOrBefore.d.test.ts
@@ -0,0 +1,6 @@
+import * as dayjs from 'dayjs'
+import * as isSameOrBefore from 'dayjs/plugin/isSameOrBefore'
+
+dayjs.extend(isSameOrBefore)
+
+dayjs('2010-10-20').isSameOrBefore('2010-10-19', 'year') === true
diff --git a/test/plugin/quarterOfYear.d.test.ts b/test/plugin/quarterOfYear.d.test.ts
new file mode 100644
index 000000000..f3f2b8ae7
--- /dev/null
+++ b/test/plugin/quarterOfYear.d.test.ts
@@ -0,0 +1,6 @@
+import * as dayjs from 'dayjs'
+import * as quarterOfYear from 'dayjs/plugin/quarterOfYear'
+
+dayjs.extend(quarterOfYear)
+
+dayjs('2013-01-01T00:00:00.000').quarter() === 1
diff --git a/types/plugin/customParseFormat.ts b/types/plugin/customParseFormat.ts
new file mode 100644
index 000000000..30ec75e5d
--- /dev/null
+++ b/types/plugin/customParseFormat.ts
@@ -0,0 +1,4 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
diff --git a/types/plugin/dayOfYear.d.ts b/types/plugin/dayOfYear.d.ts
new file mode 100644
index 000000000..028385152
--- /dev/null
+++ b/types/plugin/dayOfYear.d.ts
@@ -0,0 +1,10 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
+
+declare module 'dayjs' {
+  interface Dayjs {
+    dayOfYear(): number
+  }
+}
diff --git a/types/plugin/isSameOrAfter.d.ts b/types/plugin/isSameOrAfter.d.ts
new file mode 100644
index 000000000..12d6f889d
--- /dev/null
+++ b/types/plugin/isSameOrAfter.d.ts
@@ -0,0 +1,10 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
+
+declare module 'dayjs' {
+  interface Dayjs {
+    isSameOrAfter(date: DateType, unit?: OpUnitType): boolean
+  }
+}
diff --git a/types/plugin/isSameOrBefore.d.ts b/types/plugin/isSameOrBefore.d.ts
new file mode 100644
index 000000000..3442c69ad
--- /dev/null
+++ b/types/plugin/isSameOrBefore.d.ts
@@ -0,0 +1,10 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
+
+declare module 'dayjs' {
+  interface Dayjs {
+    isSameOrBefore(date: DateType, unit?: OpUnitType): boolean
+  }
+}
diff --git a/types/plugin/localizedFormat.d.ts b/types/plugin/localizedFormat.d.ts
new file mode 100644
index 000000000..30ec75e5d
--- /dev/null
+++ b/types/plugin/localizedFormat.d.ts
@@ -0,0 +1,4 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
diff --git a/types/plugin/quarterOfYear.d.ts b/types/plugin/quarterOfYear.d.ts
new file mode 100644
index 000000000..e8aad14b8
--- /dev/null
+++ b/types/plugin/quarterOfYear.d.ts
@@ -0,0 +1,10 @@
+import { PluginFunc } from 'dayjs'
+
+declare const plugin: PluginFunc
+export = plugin
+
+declare module 'dayjs' {
+  interface Dayjs {
+    quarter(): number
+  }
+}