diff --git a/src/app/api/upload/route.ts b/src/app/api/upload/route.ts
index 8bdd534..5977c0f 100644
--- a/src/app/api/upload/route.ts
+++ b/src/app/api/upload/route.ts
@@ -12,6 +12,7 @@ function getR2() {
     throw new Error(`Missing R2 config`);
   }
 
+  // R2 uses path-style: https://<accountId>.r2.cloudflarestorage.com/<bucket>
   return {
     client: new S3Client({
       region: "auto",
@@ -19,7 +20,7 @@ function getR2() {
       credentials: { accessKeyId, secretAccessKey: secretKey },
     }),
     bucket,
-    baseUrl: `https://${accountId}.r2.cloudflarestorage.com`,
+    baseUrl: `https://${accountId}.r2.cloudflarestorage.com/${bucket}`,
   };
 }