Matches (0)
Quick Reference
. Any character\d Digit [0-9]\w Word char\s Whitespace^ Start of line$ End of line* 0 or more+ 1 or more? 0 or 1{n} Exactly n[abc] Character set(abc) GroupFrequently Asked Questions
What is a regular expression (regex)?
A regular expression is a sequence of characters that defines a search pattern. It's used for pattern matching within strings, validation, and text manipulation.
What regex flags are supported?
g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode). Enter them in the flags field after the regex.
How do I match digits only?
Use \d for a single digit or \d+ for one or more digits. [0-9] also matches digits.
How do I match email addresses?
A simple pattern: [a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}
What does the g flag do?
The global (g) flag finds all matches instead of stopping at the first one.
Is this tool secure?
Yes! All regex testing happens in your browser. Your data never leaves your device.
How do I escape special characters?
Use backslash: \. \* \+ \? \[ \] \( \) \{ \} \^ \$ \|
What is a capturing group?
Parentheses () create groups that capture matched text. Access them via match[1], match[2], etc.
How do I match the start/end of a line?
^ matches the start, $ matches the end. With 'm' flag, they match line boundaries.
Can I use this offline?
Yes! Once loaded, the tool works completely offline in your browser.