About this regex tester
Enter a pattern and sample text to match instantly — no surrounding slashes needed. Tick the g/i/m/s/u flags and the page shows the match count live and highlights every match inside the original text; the table below lists all capture groups, and without the g flag only the first match is reported.
Invalid patterns show the exact error message so issues are easy to spot, and built-in presets for email, URL, Chinese mobile numbers, IPv4, dates and strong passwords can be inserted with one click. All matching runs locally in your browser and nothing is uploaded.