diff --git a/ext/webgpu/01_webgpu.js b/ext/webgpu/01_webgpu.js
index e9dd6c203e..d371f49ea1 100644
--- a/ext/webgpu/01_webgpu.js
+++ b/ext/webgpu/01_webgpu.js
@@ -620,7 +620,7 @@ function createGPUSupportedLimits(limits) {
 }
 
 function normalizeLimit(limit) {
-  if (typeof num === "bigint") {
+  if (typeof limit === "bigint") {
     limit = Number(limit);
     if (limit === NumberPOSITIVE_INFINITY) {
       limit = NumberMAX_SAFE_INTEGER;