What can I do with Regex Tester?

Test regular expressions, flags and capture groups live. Regex Tester is part of the Developer shelf on utils.sbs and is designed for quick, one-off tasks.

Is Regex Tester free to use?

Yes. Regex Tester is free, requires no account, and has no per-file or per-use charge.

Are my files uploaded when I use Regex Tester?

No. Regex Tester is designed to process your input locally in the browser. Files are not uploaded to a server for processing.

What formats does Regex Tester support?

It uses the browser APIs available for that task and returns the result directly in the page.

Can I use Regex Tester on my phone?

Yes. Regex Tester is responsive and works in modern mobile browsers. Very large files may be limited by the device's available memory.

Developer tool

Regex Tester

Test regular expressions, flags and capture groups live.

Runs on-deviceNo sign-upFree

All developer tools

Workspace

Regex Tester

Runs locally

Pattern

Flags

Test text

Matches

The guide

By the utils.sbs team · Reviewed November 2026 · How we build and review tools

Quick answer

Regex Tester is a free browser-based developer tool. Test regular expressions, flags and capture groups live. It runs with browser APIs locally, requires no account and does not upload your files. Open the page, add your input, adjust any options and download the result.

What is Regex Tester?

Regex Tester is a free browser-based developer tool from utils.sbs. Test regular expressions, flags and capture groups live. It is built for quick, focused jobs: open the page, add your input, adjust the options and take the result with you. No account, install or server upload is required.

At a glance

Category	Developer
Input	Depends on the tool; usually browser input or a file
Output	A result shown in the page or downloaded as a file
Engine	browser APIs
Processing	In your browser
Price	Free
Account	Not required

How Regex Tester works

This utility runs entirely in your browser and does not depend on a backend service for its result.

How to use Regex Tester

1Open Regex Tester and add your input.
2Use the default settings, or choose the format or detail level that matches your goal.
3Run the tool, check the preview or result, and download the output.

When to use Regex Tester

Handle a quick browser or system task without installing an app.
Inspect or test something directly in the current tab.
Get a focused utility result without a sign-up flow.

Limitations

Capabilities depend on the browser APIs available on the current device.

Privacy and accuracy

Regex Tester processes its input in the browser whenever the platform API allows it. Files and values are not uploaded to a server for processing, and the tool does not require an account. For calculations, use the result as a reference and verify important decisions against the source formula or a qualified professional. Read our methodology.

FAQ

Regex Tester questions

What can I do with Regex Tester?
Test regular expressions, flags and capture groups live. Regex Tester is part of the Developer shelf on utils.sbs and is designed for quick, one-off tasks.
Is Regex Tester free to use?
Yes. Regex Tester is free, requires no account, and has no per-file or per-use charge.
Are my files uploaded when I use Regex Tester?
No. Regex Tester is designed to process your input locally in the browser. Files are not uploaded to a server for processing.
What formats does Regex Tester support?
It uses the browser APIs available for that task and returns the result directly in the page.
Can I use Regex Tester on my phone?
Yes. Regex Tester is responsive and works in modern mobile browsers. Very large files may be limited by the device's available memory.

Keep going

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