diff --git a/.changeset/five-queens-tan.md b/.changeset/five-queens-tan.md
new file mode 100644
index 00000000..5be52afe
--- /dev/null
+++ b/.changeset/five-queens-tan.md
@@ -0,0 +1,7 @@
+---
+"tiktoken": patch
+"js-tiktoken": patch
+"@dqbd/tiktoken": patch
+---
+
+Add support for gpt-4o, gpt-4o-mini, text-embedding-3-small and text-embedding-3-large
diff --git a/js/src/core.ts b/js/src/core.ts
index 556eab19..7aee83fc 100644
--- a/js/src/core.ts
+++ b/js/src/core.ts
@@ -271,11 +271,16 @@ export function getEncodingNameForModel(model: TiktokenModel) {
     case "gpt-4-turbo-2024-04-09":
     case "gpt-4-turbo-preview":
     case "gpt-4-0125-preview":
-    case "text-embedding-ada-002": {
+    case "text-embedding-ada-002":
+    case "text-embedding-3-small":
+    case "text-embedding-3-large": {
       return "cl100k_base";
     }
     case "gpt-4o":
-    case "gpt-4o-2024-05-13": {
+    case "gpt-4o-2024-05-13":
+    case "gpt-4o-2024-08-06":
+    case "gpt-4o-mini-2024-07-18":
+    case "gpt-4o-mini": {
       return "o200k_base";
     }
     default:
diff --git a/tiktoken/model_to_encoding.json b/tiktoken/model_to_encoding.json
index e9bfb424..e7890e2a 100644
--- a/tiktoken/model_to_encoding.json
+++ b/tiktoken/model_to_encoding.json
@@ -20,6 +20,8 @@
     "text-davinci-edit-001": "p50k_edit",
     "code-davinci-edit-001": "p50k_edit",
     "text-embedding-ada-002": "cl100k_base",
+    "text-embedding-3-small": "cl100k_base",
+    "text-embedding-3-large": "cl100k_base",
     "text-similarity-davinci-001": "r50k_base",
     "text-similarity-curie-001": "r50k_base",
     "text-similarity-babbage-001": "r50k_base",
@@ -54,5 +56,8 @@
     "gpt-4-0125-preview": "cl100k_base",
     "gpt-4-vision-preview": "cl100k_base",
     "gpt-4o": "o200k_base",
-    "gpt-4o-2024-05-13": "o200k_base"
+    "gpt-4o-2024-05-13": "o200k_base",
+    "gpt-4o-2024-08-06":"o200k_base",
+    "gpt-4o-mini-2024-07-18": "o200k_base",
+    "gpt-4o-mini": "o200k_base"
 }
diff --git a/wasm/src/lib.rs b/wasm/src/lib.rs
index d0c1b4e0..72cb06b1 100644
--- a/wasm/src/lib.rs
+++ b/wasm/src/lib.rs
@@ -420,6 +420,9 @@ export type TiktokenModel =
     | "gpt-4-vision-preview"
     | "gpt-4o"
     | "gpt-4o-2024-05-13"
+    | "gpt-4o-2024-08-06"
+    | "gpt-4o-mini-2024-07-18"
+    | "gpt-4o-mini"
 
 /**
  * @param {TiktokenModel} encoding
@@ -436,7 +439,6 @@ pub fn encoding_for_model(
     extend_special_tokens: JsValue,
 ) -> Result<Tiktoken, JsError> {
     let encoding = match model {
-        "davinci" => Ok("p50k_base"),
         "text-davinci-003" => Ok("p50k_base"),
         "text-davinci-002" => Ok("p50k_base"),
         "text-davinci-001" => Ok("r50k_base"),
@@ -457,6 +459,8 @@ pub fn encoding_for_model(
         "text-davinci-edit-001" => Ok("p50k_edit"),
         "code-davinci-edit-001" => Ok("p50k_edit"),
         "text-embedding-ada-002" => Ok("cl100k_base"),
+        "text-embedding-3-small" => Ok("cl100k_base"),
+        "text-embedding-3-large" => Ok("cl100k_base"),
         "text-similarity-davinci-001" => Ok("r50k_base"),
         "text-similarity-curie-001" => Ok("r50k_base"),
         "text-similarity-babbage-001" => Ok("r50k_base"),
@@ -492,6 +496,9 @@ pub fn encoding_for_model(
         "gpt-4-0125-preview" => Ok("cl100k_base"),
         "gpt-4o" => Ok("o200k_base"),
         "gpt-4o-2024-05-13" => Ok("o200k_base"),
+        "gpt-4o-2024-08-06" => Ok("o200k_base"),
+        "gpt-4o-mini-2024-07-18" => Ok("o200k_base"),
+        "gpt-4o-mini" => Ok("o200k_base"),
         model => Err(JsError::new(
             format!("Invalid model: {}", model.to_string()).as_str(),
         )),