The free Regex Pattern Library & Tester
Browse a curated library of ready-made, real-world regular expressions — email, URL, IPv4, phone, hex color, date, UUID, slug and more.
- Free to use
- No signup
- Nothing to install
- Runs in your browser
Email pattern tested against "[email protected]" -> matches. Tested against "hello@example" (no top-level domain) -> no match, confirming the pattern correctly rejects an incomplete address.Open the Regex Pattern Library & Tester
Illustration. Open the tool for the real thing.
See it in action
Shown running with its default sample values
What is the Regex Pattern Library & Tester?
Writing a correct regular expression from scratch for something like email validation or a phone number is easy to get subtly wrong. This tool is a curated library of common, genuinely useful regex patterns — email address, URL, IPv4 address, US phone number, hex color code, ISO date, 24-hour time, UUID, URL-safe slug, US ZIP code and strong-password shape — each with a plain-English description of exactly what it matches and doesn't match, ready to copy straight into your code.
Click any pattern in the library and a live test box appears below it: for validation patterns like email or phone, paste a single real value and see an instant match/no-match verdict against the whole value; for the HTML-tag pattern, which searches within a larger string rather than validating a whole value, matches are highlighted inline — so either way you can confirm a pattern actually fits your real data before copying it, rather than trusting a name alone.
3 steps to your result
Open the tool and follow along. Nothing to install.
What you get
Common needs like email, URL, phone and IPv4 — not an exhaustive, overwhelming list.
Know exactly what each one matches and its real limitations.
Test any library pattern against your own real value and get a clear match/no-match result.
Copy the exact pattern string, ready to paste into your code.
AZRS tools are free to open and use.
It opens in your browser, so there is nothing to download.
Used for
Pick one to see how it fits.
Developers validating form input
Grab a correct, tested pattern instead of writing one from scratch under time pressure.
Try it freeQA engineers
Quickly verify what a given pattern will and won't match against real sample data.
Try it freeStudents learning regex
See well-described real examples rather than only abstract syntax rules.
Try it freeHow it compares
A plain look at this tool next to the usual alternative.
| This utility | Desktop software | |
|---|---|---|
| Install | Nothing to install | Usually an app or program to install |
| Account | No signup | Depends on the product |
| Cost | Free to use | Free or paid, depends on the product |
| Where it runs | In your browser tab | On your computer |
Questions people ask
Is there a single regex that perfectly validates every email address?
No — the official email spec is extremely permissive, so every practical regex (including this one) makes a reasonable tradeoff favoring real-world accuracy over matching every technically legal edge case.
Can I test my own text against these patterns?
Yes, click any pattern to open a live test box and paste your own sample text to see if and where it matches.
Are these patterns written for JavaScript specifically?
Yes, standard JavaScript regex syntax — most patterns translate directly to other languages, but double-check escaping rules for anything language-specific.
Is this the same as the site's regex tester tool?
No — the regex tester tool is for testing your own custom pattern; this is a curated library of ready-made common patterns you can browse, test and copy without writing one yourself.
Is my test text sent anywhere?
No, everything runs locally in your browser.
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Try the Regex Pattern Library & Tester now
A curated library of ready-made, real regex patterns for email, URL, phone, IPv4 and more. Free to use.
Try it free