Regex Tester
Write, test, and validate Regular Expressions against custom text strings in real-time.
Expression
//
Valid Regular Expression
Test String
6 MatchesHello World! This is a Test string with some Capitalized Words.
Match Details
Match 1Index: 0
Hello
Match 2Index: 6
World
Match 3Index: 13
This
Match 4Index: 23
Test
Match 5Index: 45
Capitalized
Match 6Index: 57
Words
Understanding Regular Expressions
Regular expressions (regex) are powerful search patterns used to match, locate, and manage text. They are universally supported across almost all programming languages.
Common Flags
- g (Global): Don't return after the first match. Find all matches.
- i (Case Insensitive): Match regardless of uppercase or lowercase.
- m (Multiline): Anchors like ^ and $ match the start and end of every line.
Common Patterns
- \d+ - Matches one or more digits
- \w+ - Matches alphanumeric words
- ^...$ - Anchors match to string boundaries
- [a-z] - Matches character classes