Regular Expressions 101

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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
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression


Test String



Code Generator

Generated Code

$re = '/(\((.*?)\))/m'; $str = 'Chats (Felis catus) Chiens (Canis lupus familiaris) Chevaux (Equus ferus caballus) Moutons (Ovis aries) Bovins (Bos taurus taurus) Porcs (Susscrofa domestica) Chèvres (Capra aegagrus hircus) Les lapins (Oryctolagus cuniculus) Les canards (Anas platyrhyncos domesticus) Les dindons (Meleagris gallopavo gallopavo) Ânes (Equus asinus) Mules (Equus asinus x Equus caballus) Chien Chat Furet Cheval âne vache lama mule Porc Cochon d\'Inde Rat domestique Hamster doré Souris domestique gerbille de Mongolie Lapin domestique Canard colvert Poule paon Pigeon tourterelle colombe Canari Perruche Poisson rouge Carpe koï axolotl '; $subst = ""; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: