diff --git a/bazel/revisions.bzl b/bazel/revisions.bzl
index 7b227c9..d72683c 100644
--- a/bazel/revisions.bzl
+++ b/bazel/revisions.bzl
@@ -2,6 +2,13 @@
 # DO NOT MODIFY
 
 EMSCRIPTEN_TAGS = {
+    "3.1.21": struct(
+        hash = "a16a8bca2466eb144f7c93fa899c0272c8815dc3",
+        sha_linux = "7045ddb3b37a2cc63cb1cf976019a6a3b7f8dbdc71254db0eee5b0452f94e9e7",
+        sha_mac = "2a8d3d3ad721fec81ca1a4a581e4183b6e732e9905beb874531851846a05a367",
+        sha_mac_arm64 = "cf788a7bdc38bb40d01f94b2d46acafb0e2f02d8ee3b3d69541c114e467ee37f",
+        sha_win = "81518bba13f41717ffe6990b6d4a5af635d0c9d0f71a8d3bc0980cd0bc8f5f66",
+    ),
     "3.1.20": struct(
         hash = "d92c8639f406582d70a5dde27855f74ecf602f45",
         sha_linux = "3b606d133489aac8cdfff4f99ff14a35563b1fafe658aa23f83694f77ed9467a",
diff --git a/emscripten-releases-tags.json b/emscripten-releases-tags.json
index 94f9e43..392c03f 100644
--- a/emscripten-releases-tags.json
+++ b/emscripten-releases-tags.json
@@ -1,6 +1,6 @@
 {
   "aliases": {
-    "latest": "3.1.20",
+    "latest": "3.1.21",
     "latest-sdk": "latest",
     "latest-arm64-linux": "3.1.9",
     "latest-64bit": "latest",
@@ -10,6 +10,8 @@
     "latest-releases-upstream": "latest"
   },
   "releases": {
+    "3.1.21": "a16a8bca2466eb144f7c93fa899c0272c8815dc3",
+    "3.1.21-asserts": "c7a387161b029621eb4d3dd57363b1393b4c50b2",
     "3.1.20": "d92c8639f406582d70a5dde27855f74ecf602f45",
     "3.1.20-asserts": "db0fd1cb7316675317d527b6ed4f4cc7005df9ec",
     "3.1.19": "4c3772879a04140298c3abde90962d5567b5e2fc",