MyAITools
Tester

Regex Tester

Regex Tester is a free online tester that helps you test a JavaScript regular expression against sample text; see matches, groups, and a replacement preview. Regex Tester uses 4 input fields, returns 3 output values, and runs in your browser on the device.

Key facts

Inputs
4 fields: Pattern, Flags, Test text, and Replacement (optional)
Outputs
3 values: Matches, Total matches, and Replacement preview
Runtime
your browser on the device
Mode
Tester
Privacy
Files and text stay in the browser session.
Cost
$0, no account required

How to use Regex Tester

  1. 1

    Paste or fill in the input

    Enter your text or values into the input fields on the page.

  2. 2

    Run the utility

    Click Compute to run the utility in your browser and review the result.

  3. 3

    Copy the output

    Copy the output value you need from the result panel.

Regex Tester details

First, enter Pattern in Regex Tester. Next, review Matches, Total matches, and Replacement preview. Additionally, Regex Tester uses 4 input fields and 3 output blocks so the result is easy to scan and copy.

Type a regex pattern and flags, paste some test text, and instantly see every match with its index and captured groups. Optionally supply a replacement string to preview what String.replace would produce. Compiled with the standard JavaScript RegExp engine and run entirely in your browser.

Common searches

  • regex tester
  • regular expression tester
  • regex matcher
  • regex playground
  • javascript regex tester
  • regex tool

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Frequently asked

What is Regex Tester?

Regex Tester is a free online tester that helps you test a JavaScript regular expression against sample text; see matches, groups, and a replacement preview. Regex Tester uses 4 input fields, returns 3 output values, and runs in your browser on the device.

What inputs and outputs does Regex Tester use?

Regex Tester uses 4 input fields: Pattern, Flags, Test text, and Replacement (optional). Regex Tester returns 3 output values: Matches, Total matches, and Replacement preview.

Do my files and data stay private?

Yes. Regex Tester runs entirely in your browser using your device's CPU. Files and text are never uploaded to our servers, so your data stays private.

How do I use Regex Tester?

Open Regex Tester, paste or fill in the input fields, and the result updates instantly. Regex Tester runs in your browser with no upload and no waiting.

Which browsers does Regex Tester support?

Any modern browser works in Chrome, Firefox, Safari, and Edge on desktop and mobile. Regex Tester uses standard web APIs and does not require any plugin, extension, or sign-up.