Regular Expressions Explained
A Regular Expression (Regex or Regexp) is a sequence of characters that specifies a search pattern in text. They are a powerful tool used for string searching, validation, and manipulation across almost all programming languages.
Our Regex Tester allows you to build and debug your expressions in real-time, providing immediate visual feedback on what your pattern matches.
Common Regex Flags
g(Global): Find all matches rather than stopping after the first match.i(Ignore Case): Make matches case-insensitive ([a-z]will also match uppercaseA-Z).m(Multiline): Changes the behavior of^and$to match the start and end of lines, rather than the start and end of the entire string.
Regex Cheatsheet
\d- Matches any digit (0-9)\w- Matches any word character (alphanumeric + underscore)\s- Matches any whitespace character.- Matches any character (except newline)+- Matches 1 or more of the preceding token*- Matches 0 or more of the preceding token?- Matches 0 or 1 of the preceding token^- Start of string/line$- End of string/line