diff --git a/src/sha256.js b/src/sha256.js
index 906663b..af99c92 100644
--- a/src/sha256.js
+++ b/src/sha256.js
@@ -17,7 +17,7 @@
     WINDOW = false;
   }
   var WEB_WORKER = !WINDOW && typeof self === 'object';
-  var NODE_JS = !root.JS_SHA256_NO_NODE_JS && typeof process === 'object' && process.versions && process.versions.node && process.type != 'renderer';
+  var NODE_JS = !root.JS_SHA256_NO_NODE_JS && !WINDOW && typeof process === 'object' && process.versions && process.versions.node && process.type != 'renderer';
   if (NODE_JS) {
     root = global;
   } else if (WEB_WORKER) {