Regular Expressions 101

Save & Manage Regex

  • Current Version: 20
  • Save & Share
  • Community Library

Flavor

  • PCRE2 (PHP)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java
  • .NET 7.0 (C#)
  • Rust
  • PCRE (Legacy)
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests
Sponsors
An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"/*.mkv") test_str = ("folder.jpg\n" "metadata\n" "Stargate SG-1 S01E01-E02 Children of the Gods.mkv\n" "Stargate SG-1 S01E03 The Enemy Within.mkv\n" "Stargate SG-1 S01E04 Emancipation.mkv\n" "Stargate SG-1 S01E05 The Broca Divide.mkv\n" "Stargate SG-1 S01E06 The First Commandment.mkv\n" "Stargate SG-1 S01E07 Cold Lazarus.mkv\n" "Stargate SG-1 S01E08 The Nox.mkv\n" "Stargate SG-1 S01E09 Brief Candle.mkv\n" "Stargate SG-1 S01E10 Thor's Hammer.mkv\n" "Stargate SG-1 S01E11 The Torment of Tantalus.mkv\n" "Stargate SG-1 S01E12 Bloodlines.mkv\n" "Stargate SG-1 S01E13 Fire and Water.mkv\n" "Stargate SG-1 S01E14 Hathor.mkv\n" "Stargate SG-1 S01E15 Singularity.mkv\n" "Stargate SG-1 S01E16 Cor-Ai.mkv\n" "Stargate SG-1 S01E17 Enigma.mkv\n" "Stargate SG-1 S01E18 Solitudes.mkv\n" "Stargate SG-1 S01E19 Tin Man.mkv\n" "Stargate SG-1 S01E20 There But For the Grace of God.mkv\n" "Stargate SG-1 S01E21 Politics (1).mkv\n" "Stargate SG-1 S01E22 Within the Serpent's Grasp (2).mkv\n") match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html