Regex Tester Online Free — Test Regular Expressions
Test regular expressions live — highlighted matches, counts, and capture groups.
Last Updated: August 2, 2026
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Open ToolHow to Use Toolza’s Free Regex Tester
Follow these simple steps to get your result in seconds.
Write a Pattern
Type your regex — from simple text to complex captures.
Paste Test Text
Add the string you want to search or match against.
Test It
Matches highlight live, with counts and positions.
Inspect Groups
See every match’s capture groups in the match list.
Why Use Toolza’s Free Tool?
Browser-based, private, and completely free — no catches.
100% Private & Secure
Your files never leave your device. All processing happens locally in your browser — no uploads, no servers, no data storage.
Completely Free
No hidden charges, no premium plans, no watermarks. Every feature is free forever.
Works on Any Device
No installation needed. Works on desktop, tablet, and mobile browsers.
No Signup Required
Start using the tool immediately. No accounts, no emails, no personal data.
High Quality Output
Results preserve original quality and formatting.
Lightning Fast
Everything runs locally, so results are instant even for large files.
Master Regex Without the Pain
Regular expressions are the most powerful text tool in computing — and the easiest to get wrong. A tester that shows you exactly what matches, where, and why turns guesswork into certainty.
What you can build with it
- Validation: Emails, phone numbers, credit cards, and passwords.
- Extraction: Pull dates, IDs, URLs, and hashtags from messy text.
- Replacement: Clean data with find-and-replace using capture groups.
- Log analysis: Filter server logs for patterns worth investigating.
Learn by seeing
The fastest way to learn regex is to experiment: write a pattern, watch the highlights, and read the match list with indices and groups. This tester was built exactly for that loop.
Frequently Asked Questions
Yes. Toolza’s regex tester is free forever with no limits.
No. Everything runs locally in your browser using JavaScript’s native RegExp engine.
Without g, only the first match is found. The g flag finds all matches and is on by default here.
JavaScript (ECMAScript). It supports lookaheads, named groups, and Unicode flags — slightly different from PCRE (PHP), so verify portability if you switch languages.
Yes, though pathological patterns on huge inputs can be slow. Output is capped at 5000 matches for performance.
Regex is greedy by default. Adding ? after quantifiers (e.g. .*?) makes them lazy, and anchors (^ $) narrow the position.
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