- Results update in real-time as you type.
- Roll over a match or expression for details.
- Save & share expressions with others.
- Explore the Library for help & examples.
- Undo & Redo with {{getCtrlKey()}}-Z / Y.
- Search for & rate Community patterns.
Regular Expression
Test String
Substitution
Replace the code without content loss
If you need to replace code with variable content mixed in, this will assist in the replacing process.Comments
Top Regular Expressions
Match string not containing string
Check if a string only contains numbers
Match elements of a url
Match an email address
Validate an ip address
Match or Validate phone number
Match html tag
Empty String
Match dates (M/D/YY, M/D/YYY, MM/DD/YY, MM/DD/YYYY)
Checks the length of number and not starts with 0
Not Allowing Special Characters
Match a valid hostname
Validate datetime
string between quotes + nested quotes
Match brackets
Match IPv6 Address
match a wide range of international phone number
Url
email validation
RegEx Allowing Number Only
Check if a string only contains numbers
Match elements of a url
Match an email address
Validate an ip address
Match or Validate phone number
Match html tag
Empty String
Match dates (M/D/YY, M/D/YYY, MM/DD/YY, MM/DD/YYYY)
Checks the length of number and not starts with 0
Not Allowing Special Characters
Match a valid hostname
Validate datetime
string between quotes + nested quotes
Match brackets
Match IPv6 Address
match a wide range of international phone number
Url
email validation
RegEx Allowing Number Only
Cheat Sheet
| Character classes | |
|---|---|
| . | any character except newline |
| \w \d \s | word, digit, whitespace |
| \W \D \S | not word, digit, whitespace |
| [abc] | any of a, b, or c |
| [^abc] | not a, b, or c |
| [a-g] | character between a & g |
| Anchors | |
| ^abc$ | start / end of the string |
| \b | word boundary |
| Escaped characters | |
| \. \* \\ | escaped special characters |
| \t \n \r | tab, linefeed, carriage return |
| \u00A9 | unicode escaped © |
| Groups & Lookaround | |
| (abc) | capture group |
| \1 | backreference to group #1 |
| (?:abc) | non-capturing group |
| (?=abc) | positive lookahead |
| (?!abc) | negative lookahead |
| Quantifiers & Alternation | |
| a* a+ a? | 0 or more, 1 or more, 0 or 1 |
| a{5} a{2,} | exactly five, two or more |
| a{1,3} | between one & three |
| a+? a{2,}? | match as few as possible |
| ab|cd | match ab or cd |
