Regular Expressions 101

@regex101
Donate
Sponsor
Contact
Bug Reports & Feedback
Wiki
Whats new?

Save & Share

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

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python 2.7
  • Golang (RE2)

Function

  • Match
  • Substitution
  • List
  • Unit Tests
"
view_cat(?:\.php)?\?cat=(.+)&(type)=(.+)
"
g
view_cat matches the characters view_cat literally (case sensitive)
Non-capturing group
(?:\.php)?
? Quantifier — Matches between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . literally (case sensitive)
php matches the characters php literally (case sensitive)
\? matches the character ? literally (case sensitive)
cat= matches the characters cat= literally (case sensitive)
1st Capturing Group
(.+)
.+
matches any character (except for line terminators)
+ Quantifier — Matches between one and unlimited times, as many times as possible, giving back as needed (greedy)
& matches the character & literally (case sensitive)
2nd Capturing Group
(type)
type matches the characters type literally (case sensitive)
= matches the character = literally (case sensitive)
3rd Capturing Group
(.+)
.+
matches any character (except for line terminators)
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

r"
"
g

Test String

Substitution

Processing...