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JavaScript Error Fixer

Paste your JavaScript code and instantly detect & fix common errors — const/let issues, missing semicolons, undefined variables, and more.

💡 Try Example

Click below to load sample code with common JS errors and see them auto-fixed.

About

JavaScript Error Fixer is a free online tool that analyzes your JavaScript code and automatically detects and fixes common errors. It catches issues like const reassignment, var usage, missing semicolons, typos in common APIs (console.log, document), and loose equality comparisons.

Perfect for beginners learning JavaScript, developers debugging quick scripts, or anyone who needs a fast code review. All analysis runs entirely in your browser — no code is sent to any server, keeping your code completely private.

Simply paste your code, click "Analyze & Fix", and get an instant report of all issues found along with the corrected code ready to copy. Try the example to see it in action.

Upgrade to Pro

Unlimited usage, bulk processing, API access & priority support — €9/month

Free

  • ✓ 5 uses per day
  • ✓ Basic features
  • ✗ No bulk processing
  • ✗ No API access

Pro

  • ✓ Unlimited uses
  • ✓ All features unlocked
  • ✓ Bulk processing
  • ✓ API access
Get Pro Access →

Cancel anytime. Secure payment via Stripe.

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