Test Regular Expression Online

Regex Tester is a free online Regex Tools tool that live JavaScript regex testing with match groups highlighted instantly in your browser. Paste your data, adjust the options and get the result in real time — no installation, no sign-up, and nothing is ever uploaded to a server. No download or account is required: the tool loads in under a second and works offline-friendly after the first visit.

How to use

Using Regex Tester takes three steps:

  1. Paste your data into the input box (or load the example).
  2. Configure the options to match your target format or scenario.
  3. Copy, download or inspect the output — it updates live as you type.
  4. No download or account is required: the tool loads in under a second and works offline-friendly after the first visit.

Examples

[email protected] and [email protected]

Use cases

  • Live JavaScript regex testing with match groups highlighted.
  • Because everything is computed client-side, Regex Tester is safe to use with sensitive data such as API keys, tokens or private logs.

FAQ

What is Regex Tester?

Regex Tester live JavaScript regex testing with match groups highlighted. It runs entirely in your browser, so your data stays private.

Is Regex Tester free to use?

Yes. Regex Tester is free, unlimited and works without registration or installation.

Does my data get uploaded?

No. All processing happens locally in your browser; nothing is sent to any server.

Runs 100% in your browser — your data never leaves your device.

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