Developer ToolsCode ValidatorsFree Tool
Regular Expression Validator
Check whether a regular expression pattern compiles without a syntax error, using the JavaScript regex engine.
How to Use Regular Expression Validator
- 1Paste your regex pattern (without the surrounding slashes)
- 2Click Process
- 3Read the valid/invalid result and any error message
Frequently Asked Questions
It tries to construct a JavaScript RegExp object from your input; if construction succeeds, the pattern is syntactically valid. If it throws, the exact error message is shown.
No — this only checks syntax validity, not matching behavior. Use the Regex Tester or Regex Debugger tools to test a pattern against actual text.
No — it uses JavaScript's regex engine specifically. Syntax that's valid in other regex flavors (like some named-group variations) may behave differently or error here.
No — validation runs entirely in your browser.
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