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

r"
"
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"\S+\.(?:png|jpe?g|gif|bmp|mp4|avi|flv)\b" test_str = ("/mnt/data/Content:\n" "ManifestFile.txt kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4 tmp_content\n" "default_55a655f340908dce55d10a191b6a0140 price-tags_b3c756dda783ad0691163a900fb5fe15\n\n" "/mnt/data/Content/default_55a655f340908dce55d10a191b6a0140:\n" "LayoutFile_34450b33c8b44af409abb057ddedfdfe.txt blank_decommissioned.jpeg tmp_content\n" "ManifestFile.txt blank_unregistered.png\n\n" "/mnt/data/Content/default_55a655f340908dce55d10a191b6a0140/tmp_content:\n\n" "/mnt/data/Content/kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4:\n" "0001111084948-kompass-LARGE.avi 0076738703404-kompass-LARGE.png LayoutFile_7c1b3793e49204982e0e41923303c17b.txt\n" "0001111087321-kompass-LARGE.jpg 0076738703419-kompass-LARGE.mp4 ManifestFile.txt\n" "0001111087325-kompass-LARGE.png 0076738703420-kompass-LARGE.png tmp_content\n\n" "/mnt/data/Content/kompass-tags_e2d5dac5ba548a1206b5d40f58e448e4/tmp_content:\n\n" "/mnt/data/Content/price-tags_b3c756dda783ad0691163a900fb5fe15:\n" "0001111084948-consumer-large.png 0076738703404-consumer-large.png LayoutFile_a694b1e05d08705aaf4dd589ac61d493.txt\n" "0001111087321-consumer-large.png 0076738703419-consumer-large.avi ManifestFile.txt\n" "0001111087325-consumer-large.mp4 0076738703420-consumer-large.png tmp_content\n\n" "/mnt/data/Content/price-tags_b3c756dda783ad0691163a900fb5fe15/tmp_content:\n\n" "/mnt/data/Content/tmp_content:") 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