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
    [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
No Match

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\[.*?\)" test_str = "Steps:\\n\\n[Step as , asdasd . sd32 'd](http://dev.nzfood-site.wn.bauer-media.net.au/silver-fern-farms-competition-21001) 1 Preheat oven to 120°C. Arrange six 1 1/2-cup ramekins in large baking dish lined [with](http://dev.nzfood-site.wn.bauer-media.net.au/silver-fern-farms-competition-21001) a cloth. \\nStep 2 In a medium saucepan, combine cream and vanilla. Place over medium heat and bring to almost boiling point. \\nStep 3 Meanwhile, in a bowl, whisk yolks and sugar together until thick and pale. Gradually pour in hot cream mixture, whisking constantly. \\nStep 4 Return mixture to clean saucepan. Cook on low heat 10-12 minutes, stirring constantly until thick enough to just coat the back of a wooden spoon (be careful not to overheat or mixture will curdle). \\nStep 5 Divide custard between ramekins. Pour boiling water into baking dish to come halfway up sides of ramekins. Bake 20-25 minutes until almost set and slightly wobbly in centre. Remove ramekins. \\nStep 6 Cool completely in fridge. Just before serving, sprinkle custards with an even layer of raw sugar. Using a kitchen blowtorch, drag the flame back and forth over the sugar until caramelised." matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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