Regex Tester

Test and debug regular expressions with real-time match highlighting, capture groups, and flag options. Essential for form validation and text parsing.

Files never leave your device Always free No server uploads No sign-up No watermarks

Processing happens on your device — nothing is uploaded.

How It Works

Enter your regex pattern

Type your regular expression in the pattern field. Flags like g, i, m can be toggled.

Matches highlight live

Paste test text below and matches highlight instantly as you type your pattern.

Check match details

See capture groups, match count, and positions. No external server is involved.

Frequently Asked Questions

What is Regex Tester?

Regex Tester is a free, browser-based tool on TitanFile that lets you test and debug regular expressions with real-time match highlighting, capture groups, and flag options. Essential for form validation and text parsing. Everything runs locally on your device — no files are ever uploaded to any server.

How do I use Regex Tester?

Open the Regex Tester page, add your file or enter your data, adjust any settings, then click the action button. Your result is ready instantly — no sign-up or installation required.

Are my files private?

Yes — all processing happens entirely in your browser using JavaScript. Your files and data never leave your device and are never uploaded to any server. We cannot see your files even if we wanted to.

Does this work offline?

Once the page has loaded, Regex Tester works without an internet connection. You can install it as a PWA to your home screen for instant offline access.

Is there a file size limit?

There is no server-side limit because everything runs locally in your browser. The practical limit is your device's available memory. Most modern devices handle files up to several hundred MB without issue.

Why is this free?

TitanFile is ad-supported and passion-driven. We believe powerful tools should be accessible to everyone. Regex Tester — like every tool on TitanFile — will always be free with no paywalls, watermarks, or hidden fees.