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"(?=.*:10:)(?=.*] 500 )" test_str = ("10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/signlangreasons HTTP/1.1\" C9F41ED8235AADD69F997704FC55513A [-] 200 378 9ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/cases/statuses?actionType=service HTTP/1.1\" E325D41D75BB121D44750BCE16C26A62 [-] 200 296 12ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/readreasons HTTP/1.1\" C9F41ED8235AADD69F997704FC55513A [-] 200 452 15ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/ate/regions HTTP/1.1\" 5B781DAF2A0E25E64BEC52ED4DC95A23 [-] 200 216 7ms Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.80 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/translationreasons HTTP/1.1\" C9F41ED8235AADD69F997704FC55513A [-] 200 260 18ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/capabilities?lang=RU HTTP/1.1\" C9F41ED8235AADD69F997704FC55513A [-] 200 395 21ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/signreasons HTTP/1.1\" C9F41ED8235AADD69F997704FC55513A [-] 200 446 22ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/members/types HTTP/1.1\" 5B781DAF2A0E25E64BEC52ED4DC95A23 [-] 200 291 13ms Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.80 Safari/537.36\n" "10.0.2.16 [20/Dec/2023:10:56:22 +0300] \"GET /notariat-ais/api/cases/billStatuses HTTP/1.1\" E325D41D75BB121D44750BCE16C26A62 [-] 200 266 12ms Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36\n") 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