DEVELOPER TOOLS · LOCAL ONLY
Test regular expressions and load ready-made Email, URL, and IP patterns.
Test text up to 100,000 characters, up to 1,000 matches shown, about 800ms execution limit.
Run the tool to see the result
Test text up to 100,000 characters, up to 1,000 matches shown, about 800ms execution limit.
| Matches | Pattern | Example | Use |
|---|---|---|---|
^[\w.+-]+@[\w-]+\.[a-zA-Z]{2,}$ | [email protected] | ||
| URL | ^https?:\/\/[\w.-]+\.[a-zA-Z]{2,}(?:\/[\w\-./?%&=#]*)?$ | https://tooloo.app/path | |
| IPv4 | ^(?:(?:25[0-5]|2[0-4]\d|1?\d?\d)\.){3}(?:25[0-5]|2[0-4]\d|1?\d?\d)$ | 192.168.0.1 | |
| Phone (TW) | ^09\d{2}-?\d{3}-?\d{3}$ | 0912-345-678 | |
| ISO Date | ^\d{4}-\d{2}-\d{2}$ | 2026-09-04 | |
| Hex Color | ^#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})$ | #3157d5 | |
| Username | ^[a-zA-Z][a-zA-Z0-9_]{2,15}$ | tooloo_dev | |
| Postal Code (TW) | ^\d{3}(?:\d{2})?$ | 10646 |
How to use
Run your expression in a time-limited Worker and list every match. Common patterns for email, URL, IPv4, dates, and hex colours sit below the workspace: click one to load it into the pattern field and adjust from there, without visiting another page. The Worker time limit means even a catastrophically backtracking pattern cannot freeze the tab.
Limits and privacy
Everything runs inside this browser. Your input is never uploaded, stored, or written to the URL or any log.