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
/
^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])[a-zA-Z0-9]{6,}$
/
gm
^ asserts position at start of a line
Positive Lookahead
(?=.*[a-z])
Assert that the Regex below matches
.*
matches any character (except for line terminators)
* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[a-z]
a-z a single character in the range between a (index 97) and z (index 122) (case sensitive)
Positive Lookahead
(?=.*[A-Z])
Assert that the Regex below matches
.*
matches any character (except for line terminators)
* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[A-Z]
A-Z a single character in the range between A (index 65) and Z (index 90) (case sensitive)
Positive Lookahead
(?=.*[0-9])
Assert that the Regex below matches
.*
matches any character (except for line terminators)
* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[0-9]
0-9 a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
Match a single character present in the list below
[a-zA-Z0-9]{6,}
{6,} Quantifier — Matches between 6 and unlimited times, as many times as possible, giving back as needed (greedy)
a-z a single character in the range between a (index 97) and z (index 122) (case sensitive)
A-Z a single character in the range between A (index 65) and Z (index 90) (case sensitive)
0-9 a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String