Regular Expressions 101

Save & Share

  • Save Regex
    ctrl+s
  • Update Regex
    ctrl+⇧+s

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8

Function

  • Match
  • Substitution
  • List
  • Unit Tests
/
(([^<>()\[\]\.,;:\s@\"]+(\.[^<>()\[\]\.,;:\s@\"]+)*)|(\".+\"))@(([^<>()\.,;\s@\"]+\.{0,1})+([^<>()\.,;:\s@\"]{2,}|[\d\.]+))
/
g
1st Capturing Group
(([^<>()\[\]\.,;:\s@\"]+(\.[^<>()\[\]\.,;:\s@\"]+)*)|(\".+\"))
1st Alternative
([^<>()\[\]\.,;:\s@\"]+(\.[^<>()\[\]\.,;:\s@\"]+)*)
2nd Capturing Group
([^<>()\[\]\.,;:\s@\"]+(\.[^<>()\[\]\.,;:\s@\"]+)*)
Match a single character not present in the list below
[^<>()\[\]\.,;:\s@\"]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
<>()
matches a single character in the list <>() (case sensitive)
\[ matches the character [ with index 9110 (5B16 or 1338) literally (case sensitive)
\] matches the character ] with index 9310 (5D16 or 1358) literally (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
,;:
matches a single character in the list ,;: (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
@ matches the character @ with index 6410 (4016 or 1008) literally (case sensitive)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
3rd Capturing Group
(\.[^<>()\[\]\.,;:\s@\"]+)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
Match a single character not present in the list below
[^<>()\[\]\.,;:\s@\"]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
<>()
matches a single character in the list <>() (case sensitive)
\[ matches the character [ with index 9110 (5B16 or 1338) literally (case sensitive)
\] matches the character ] with index 9310 (5D16 or 1358) literally (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
,;:
matches a single character in the list ,;: (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
@ matches the character @ with index 6410 (4016 or 1008) literally (case sensitive)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
2nd Alternative
(\".+\")
4th Capturing Group
(\".+\")
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
.
matches any character (except for line terminators)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
@ matches the character @ with index 6410 (4016 or 1008) literally (case sensitive)
5th Capturing Group
(([^<>()\.,;\s@\"]+\.{0,1})+([^<>()\.,;:\s@\"]{2,}|[\d\.]+))
6th Capturing Group
([^<>()\.,;\s@\"]+\.{0,1})+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character not present in the list below
[^<>()\.,;\s@\"]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
<>()
matches a single character in the list <>() (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
,;
matches a single character in the list ,; (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
@ matches the character @ with index 6410 (4016 or 1008) literally (case sensitive)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
\.
matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
{0,1} matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
7th Capturing Group
([^<>()\.,;:\s@\"]{2,}|[\d\.]+)
1st Alternative
[^<>()\.,;:\s@\"]{2,}
Match a single character not present in the list below
[^<>()\.,;:\s@\"]
{2,} matches the previous token between 2 and unlimited times, as many times as possible, giving back as needed (greedy)
<>()
matches a single character in the list <>() (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
,;:
matches a single character in the list ,;: (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
@ matches the character @ with index 6410 (4016 or 1008) literally (case sensitive)
\" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
2nd Alternative
[\d\.]+
Match a single character present in the list below
[\d\.]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\d matches a digit (equivalent to [0-9])
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.

Regular Expression
No Match

/
/
g

Test String

Code Generator

Generated Code

Loading code sample...
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/