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Regex Tester
Test and debug regular expressions as you type. See matches highlighted, view match details, and test find-replace operations.
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Flags:
Common patterns
Quick reference
. Any character\d Digit [0-9]\w Word char\s Whitespace^ Start of string$ End of string* 0 or more+ 1 or more? 0 or 1{n} Exactly n[abc] Character class() Capture groupWhat are Regular Expressions?
Regular expressions (regex) are patterns that match character combinations in strings. You use them to search, validate, and manipulate text.
Common flags
gGlobal: find all matches, not just the firstiCase insensitive: ignore case when matchingmMultiline: ^ and $ match line boundariessDotall: . matches newline characters
Basic syntax
.Any single character\dAny digit (0-9)\wWord characters (a-z, A-Z, 0-9, _)\sWhitespace*0 or more of preceding+1 or more of preceding?0 or 1 of preceding[abc]Any char in bracketsCommon use cases
- •Validating email addresses, phone numbers, URLs
- •Extracting data from log files
- •Search and replace in code editors
- •Form input validation
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