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JavaScript Syntax Validator

Check JavaScript for syntax errors using the latest ECMAScript grammar, with line, column and a code frame.

Runs in your browserJavaScript → Report
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Example

Input
const total = items.reduce((a, b) => a + b, 0;
Output
✗ SyntaxError

Line 1, column 46: Unexpected token

1 | const total = items.reduce((a, b) => a + b, 0;
  |                                              ^

How to use the JavaScript Syntax Validator

  1. Paste or type your JavaScript into the input area, or open a file from your device.
  2. Adjust the options above the editor if the tool offers any.
  3. Review the Report result, then copy it or download it as a file.

Privacy and limitations

  • Your data is processed on your device and is not uploaded to any server.
  • Only syntax is checked. JSX and TypeScript syntax are not supported, and code is never executed.

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