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Developer tools / Regex Tester
Regex Tester
Test regular expressions, flags, matches, groups and replacements safely.
Processed locallyYour files never leave your device.
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Built for the task
Fast, focused and private.
What this tool does
Test JavaScript regular expressions locally with match groups, flags, replacement output and execution safeguards.
How privacy works
The input stays on this device. Processing begins only after you interact with the workspace, and the page does not contain a file-upload endpoint.
Frequently asked questions
Is Regex Tester free?
Yes. The tool is free to use and does not require an account.
Is my data uploaded?
No. This tool performs its work locally in your browser. Your input is not sent to NimbleWebTools.
What happens when I close the page?
Inputs and generated results are held by the current browser tab. Temporary download URLs are released when the page closes or resets.
Which browsers are supported?
Use a current browser with modern JavaScript and Web API support. The page reports a clear error when a required capability or format is unavailable.