Regex Tester: quick start guide

Everything you need for a first successful run: what to paste in, which option actually matters, and how to read the result.

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

  1. Open the tool and paste your input into the left pane.
  2. Set only the options your task actually needs — the defaults are correct for most inputs.
  3. Read the result in the right pane; it updates as you type.
  4. Use Copy to take the result, or Download to save it as a file.
How to use · Regex Tester 1 Paste your data intothe input box (or loadthe example). 2 Configure the optionsto match your targetformat or scenario. 3 Copy, download orinspect the output —it updates live as youtype.
How to use — 3

Examples

Try email pattern.

Input

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

Output — Results

<p class="tb-note">2 matches</p><table class="tb-table"><tr><th>#</th><th>Match</th><th>Index</th></tr><tr><td>1</td><td><code>user-2026@mail.com</code></td><td>0</td></tr><tr><td>2</td><td><code>admin@sub.example.co.uk</code></td><td>23</td></tr></table><pre class="ex-io"><mark>user-2026@mail.com</mark> and <mark>admin@sub.example.co.uk</mark></pre>

Run

Description

Live JavaScript regex testing with match groups highlighted.

Regex Tester → · How to use → · Regex Tools →

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