Regex Tester
Test regular expressions against any string. See matches highlighted in real time with capture group details.
Runs locally in your browser — nothing you type is sent anywhere.
Get better results
Tips from how Regex Tester actually works, and mistakes worth avoiding.
Pro tips
- Keep a working copy of your input before running a destructive operation — undo is a browser back-button, not a history stack.
- When something looks wrong, check the start of the input first — most parsing errors cascade from one early character.
- Bookmark this page. It is a static URL with no login, so it works the same way every time you need it.
Common mistakes
- Assuming a paid tool would give a more "official" result — the underlying parsing logic is the same either way.
- Not checking for trailing commas, smart quotes, or copy-pasted invisible characters — the most common source of a confusing error.
- Working directly on the only copy of an important file instead of a duplicate.
Frequently asked questions
About Regex Tester and how Tarumak Studio works.
What regex syntax does this tool use?
JavaScript's built-in RegExp engine, which follows ECMAScript standards. Most standard regex syntax (character classes, quantifiers, groups, lookaheads) is supported.
What do the g, i, and m flags do?
g (global) finds all matches not just the first. i makes the pattern case-insensitive. m makes ^ and $ match the start and end of each line rather than the whole string.
Can I test capture groups?
Yes — the first match's capture groups ($1, $2, etc.) are displayed below the test string.
Is Regex Tester really free?
Yes — completely free, with no usage limits, no watermarks and no premium wall. Every tool on Tarumak Studio is free to use.
Do I need to create an account?
No. There is no sign-up, no login and no email required. Open the tool and use it immediately.
Is my input sent to a server?
No. Regex Tester processes everything you type or paste locally in your browser — nothing is ever sent to a server.
Does it work on mobile?
Yes. The tool runs in any modern browser on desktop, tablet or phone — no app install needed.
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