diff --git a/web/js/proof-of-work-slow.mjs b/web/js/proof-of-work-slow.mjs
index a1be6ea..69ef5a8 100644
--- a/web/js/proof-of-work-slow.mjs
+++ b/web/js/proof-of-work-slow.mjs
@@ -70,7 +70,7 @@ function processTask() {
       let hash;
       let nonce = 0;
       do {
-        if (nonce & (1023 === 0)) {
+        if ((nonce & 1023) === 0) {
           postMessage(nonce);
         }
         hash = await sha256(data + nonce++);