To do this in any ES5-compatible environment, such as Node.js, Chrome, Internet Explorer 9+, Firefox 4+, or Safari 5+:
Object.keys(obj).length
- Browser compatibility
- Object.keys documentation (includes a method you can add to non-ES5 browsers)
To do this in any ES5-compatible environment, such as Node.js, Chrome, Internet Explorer 9+, Firefox 4+, or Safari 5+:
Object.keys(obj).length