- 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
Private IP Tester
This regex string tests whether or not an IP address is in the private IP address range. If the inputted address or addresses are highlighted, then they are in the private IP address range.Comments
Top Regular Expressions
Url checker with or without http:// or https://
Match string not containing string
Check if a string only contains numbers
Only letters and numbers
Match elements of a url
Url Validation Regex | Regular Expression - Taha
Match an email address
Validate an ip address
nginx test
match whole word
Match or Validate phone number
Match html tag
Find Substring within a string that begins and ends with paranthesis
Blocking site with unblocked games
Match dates (M/D/YY, M/D/YYY, MM/DD/YY, MM/DD/YYYY)
Empty String
Match if doesn't start with string
Checks the length of number and not starts with 0
all except word
Match a valid hostname
Match string not containing string
Check if a string only contains numbers
Only letters and numbers
Match elements of a url
Url Validation Regex | Regular Expression - Taha
Match an email address
Validate an ip address
nginx test
match whole word
Match or Validate phone number
Match html tag
Find Substring within a string that begins and ends with paranthesis
Blocking site with unblocked games
Match dates (M/D/YY, M/D/YYY, MM/DD/YY, MM/DD/YYYY)
Empty String
Match if doesn't start with string
Checks the length of number and not starts with 0
all except word
Match a valid hostname
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 |
