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"( \(\d{4}_\d{2}_\d{2} \d{2}_\d{2}_\d{2} \w{3}\))+|\1.\w{3}\n" test_str = ("\n" "Acacia tree 2 (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "Acacia tree 2 (2015_12_03 14_18_17 UTC).jpg\n" "JOURNEY TO ARABIA (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "Acacia Tree 4 (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n\n\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\AFRICA THE MOTHER OF US ALL 3 (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\AFRICAN MAN + CROCODILE (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\AFRICAN MAN + CROCODILE (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\AFRICAN MAN + CROCODILE (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\African muslim with favorite slave (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\African muslim with favorite slave (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\African muslim with favorite slave (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amagufwa ya bene Rwanda (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amagufwa ya bene Rwanda (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amagufwa ya bene Rwanda (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ama-Rank y' inyenzi (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ama-Rank y' inyenzi (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ama-Rank y' inyenzi (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (1) (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (1) (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (1) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Amenhotep_III (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amenhotep3_head_03 (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amenhotep3_head_03 (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\amenhotep3_head_03 (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman] (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman] (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman] (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman]2 (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman]2 (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\an Egyptian [Sudanese woman]2 (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient Africa How Europeans have it wrong - Kevin MacDonald (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient Africa How Europeans have it wrong - Kevin MacDonald (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient Africa How Europeans have it wrong - Kevin MacDonald (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African script (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African script (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African script (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient African Scripts (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient African Scripts (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Ancient African Scripts (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African writings (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African writings (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ancient African writings (2015_12_03 14_18_17 UTC).png\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\ANCIENT HEBREWS DWELLINGS (2014_10_06 13_06_05 UTC) \n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Bamwe mu basigajwe inyuma n’amateka bo mu Mudugudu wa Bukamba - LEVITES (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Baobab (Adansonia digitata) and elephant, Tanzania (2014_10_06 13_06_05 UTC) (2015_12_03 14_18_17 UTC).jpg\n" "D:\\Kmna\\Desktop\\FACE-PICTS\\RAW MATERIALS\\Baobab (Adansonia digitata) and elephant, Tanzania (2014_10_15 02_10_34 UTC) (2015_12_03 14_18_17 UTC).jpg") 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