Ready-Made Presets (Click to Load):
Visual Highlight
How it works
1
Type or paste your Regex pattern and toggle flags (g, i, m, s, u).
2
Enter your test string or click any ready-made preset (Email, CPF, CEP, URLs, Dates).
3
Inspect visually highlighted matches and explore the detailed list of captured groups.
4
Use the substitution tab to test text replacements and refer to the cheatsheet for quick syntax lookups.
Frequently asked questions
Is it really free?
Yes. The site is supported by ads, so you never pay or need to create an account.
Are my test strings uploaded to a server?
Never. All regular expression processing runs entirely in your browser's local JavaScript engine, ensuring zero latency and absolute privacy.
Which regex flags are available?
All standard ECMAScript flags: 'g' (global), 'i' (case-insensitive), 'm' (multiline), 's' (dotAll), and 'u' (unicode).
Can I test substitutions with captured groups?
Yes! Use the substitution tab with replacement tokens such as $1, $2, or $& to reformat text instantly.
Does it work on mobile?
Yes. The page adapts to your screen and does not require installing any app.