How to use: Regex Tester

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.

Input Regex Tester Output Runs 100% in your browser — your data never leaves your device.
Regex Tester — Input → Output. Runs 100% in your browser — your data never leaves your device.

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.
How to use · Regex Tester 1 Input Paste your data intothe input box (or loadthe example). 2 Options Configure the optionsto match your targetformat or scenario. 3 Output Copy, download orinspect the output —it updates live as youtype.
How to use — 3

Description

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.

Run

These ready-made examples show typical inputs and the exact output Regex Tester produces for them.

Examples

Try email pattern.

user-2026@mail.com and admin@sub.example.co.uk

Use cases

Common situations where Regex Tester helps:

  • 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.

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