diff --git a/tokenizers/src/models/bpe/model.rs b/tokenizers/src/models/bpe/model.rs
index 25efc691c..ac31fc8a8 100644
--- a/tokenizers/src/models/bpe/model.rs
+++ b/tokenizers/src/models/bpe/model.rs
@@ -1,7 +1,9 @@
-use super::{Cache, Error, Pair, WithFirstLastIterator, Word, DEFAULT_CACHE_CAPACITY};
+use super::{
+    super::OrderedVocabIter, Cache, Error, Pair, WithFirstLastIterator, Word,
+    DEFAULT_CACHE_CAPACITY,
+};
 use crate::tokenizer::{Model, Offsets, Result, Token};
 use rand::{thread_rng, Rng};
-use serde::{Serialize, Serializer};
 use serde_json::Value;
 use std::{
     collections::HashMap,
@@ -463,28 +465,6 @@ impl Model for BPE {
     }
 }
 
-/// Wraps a vocab mapping (ID -> token) to a struct that will be serialized in order
-/// of token ID, smallest to largest.
-struct OrderedVocabIter<'a> {
-    vocab_r: &'a HashMap<u32, String>,
-}
-
-impl<'a> OrderedVocabIter<'a> {
-    fn new(vocab_r: &'a HashMap<u32, String>) -> Self {
-        Self { vocab_r }
-    }
-}
-
-impl<'a> Serialize for OrderedVocabIter<'a> {
-    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: Serializer,
-    {
-        let iter = (0u32..(self.vocab_r.len() as u32)).map(|i| (&self.vocab_r[&i], i));
-        serializer.collect_map(iter)
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/tokenizers/src/models/mod.rs b/tokenizers/src/models/mod.rs
index e1a2ad8f0..baab582b3 100644
--- a/tokenizers/src/models/mod.rs
+++ b/tokenizers/src/models/mod.rs
@@ -3,3 +3,28 @@
 pub mod bpe;
 pub mod wordlevel;
 pub mod wordpiece;
+
+use serde::{Serialize, Serializer};
+use std::collections::HashMap;
+
+/// Wraps a vocab mapping (ID -> token) to a struct that will be serialized in order
+/// of token ID, smallest to largest.
+struct OrderedVocabIter<'a> {
+    vocab_r: &'a HashMap<u32, String>,
+}
+
+impl<'a> OrderedVocabIter<'a> {
+    fn new(vocab_r: &'a HashMap<u32, String>) -> Self {
+        Self { vocab_r }
+    }
+}
+
+impl<'a> Serialize for OrderedVocabIter<'a> {
+    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let iter = (0u32..(self.vocab_r.len() as u32)).map(|i| (&self.vocab_r[&i], i));
+        serializer.collect_map(iter)
+    }
+}
diff --git a/tokenizers/src/models/wordlevel/mod.rs b/tokenizers/src/models/wordlevel/mod.rs
index b7bb12fac..c05861d71 100644
--- a/tokenizers/src/models/wordlevel/mod.rs
+++ b/tokenizers/src/models/wordlevel/mod.rs
@@ -1,3 +1,4 @@
+use super::OrderedVocabIter;
 use crate::tokenizer::{Model, Result, Token};
 use serde_json::Value;
 use std::collections::HashMap;
@@ -168,20 +169,14 @@ impl Model for WordLevel {
             None => "vocab.json".to_string(),
         };
 
-        // Write vocab.txt
+        // Write vocab.json
         let vocab_path: PathBuf = [folder, Path::new(vocab_file_name.as_str())]
             .iter()
             .collect();
         let mut vocab_file = File::create(&vocab_path)?;
-        let mut vocab: Vec<(&String, &u32)> = self.vocab.iter().collect();
-        vocab.sort_unstable_by_key(|k| *k.1);
-        vocab_file.write_all(
-            &vocab
-                .into_iter()
-                .map(|(token, _)| format!("{}\n", token).as_bytes().to_owned())
-                .flatten()
-                .collect::<Vec<_>>()[..],
-        )?;
+        let order_vocab_iter = OrderedVocabIter::new(&self.vocab_r);
+        let serialized = serde_json::to_string(&order_vocab_iter)?;
+        vocab_file.write_all(&serialized.as_bytes())?;
 
         Ok(vec![vocab_path])
     }
diff --git a/tokenizers/src/models/wordpiece/mod.rs b/tokenizers/src/models/wordpiece/mod.rs
index 8bb8c6541..3c93e62a2 100644
--- a/tokenizers/src/models/wordpiece/mod.rs
+++ b/tokenizers/src/models/wordpiece/mod.rs
@@ -252,8 +252,8 @@ impl Model for WordPiece {
 
     fn save(&self, folder: &Path, name: Option<&str>) -> Result<Vec<PathBuf>> {
         let vocab_file_name = match name {
-            Some(name) => format!("{}-vocab.json", name),
-            None => "vocab.json".to_string(),
+            Some(name) => format!("{}-vocab.txt", name),
+            None => "vocab.txt".to_string(),
         };
 
         // Write vocab.txt