91
Press any key to get the JavaScript event keycode
{ "key": "Meta", "keyCode": 91, "which": 91, "code": "MetaLeft", "location": 1, "altKey": false, "ctrlKey": false, "metaKey": true, "shiftKey": false, "description": "Windows Key / Left ⌘ / Chromebook Search key", "unicode": "⌘ ⊞" }