JavaScript Validator

Check JavaScript syntax using the browser parser.

JavaScript Validator uses the browser’s parser to catch basic syntax problems before you run code in the preview.

Input

Output

When to use JavaScript Validator

Checking a snippet for missing braces
Validating student submissions quickly
Smoke-testing edits before Run in the compiler

Example

const x = 1;
console.log(x);

Benefits

Free to use—no account required
Runs in your browser
Instant results with no software install
Basic processing does not upload your content to a server
Passing syntax checks does not prove runtime correctness—still test behavior.

Not the same as

This is not a linter for style rules. JSON has its own validator tool.

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