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

/
/
gm

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]?\s*\(?\d{3}\)?[\s\.-]?\d{3}[\s\.-]?\d{4}" test_str = ("Task: Return only the residents of Spencerport, NY who have phone numbers listed. Include the name, address and phone number of the individual(s).\n" "----------------------------------------------------------------\n" "Public Records and Phone Records Listings\n\n" "DEFRANK, EDMUND\n" "823 WASHINGTON ST, SPENCERPORT, NY 14559-9703.\n" "Phone Number 585-352-9218\n\n\n" "ODELL, E\n" "BRIGHTON, NY 12970.\n" "Phone Number 585-327-3686\n\n\n" "DEFRANCO, FRANK\n" "6 REX LN, SPENCERPORT, NY 14559-9700\n\n\n" "DR. OBRECT, MICHAEL\n" "200 RED CREEK DR, HENRIETTA, NY 14467\n" "Phone Number +1 (585) 334-0352\n\n\n" "FRANCIS, PAUL\n" "37 TROTTER DR, HENRIETTA, NY 14467-9769.\n" "Phone Number 585-334-7733\n\n\n" "CARLSON, BRITA\n" "1 BURKE LN #D, SPENCERPORT, NY 14559-1546.\n" "Phone Number +1 (585) 3529383\n\n\n" "EDWARDS, SUSAN\n" "4621 W RIDGE RD, SPENCERPORT, NY 14559-1552.\n" "Phone Number \n\n\n" "CARLSON, JEFF\n" "21 NEVINS RD, HENRIETTA, NY 14467-9307.\n" "Phone Number 585-359-9545\n\n\n" "FRANCIS, RICHARD\n" "13 LINDA LN, SPENCERPORT, NY 14559-1613. \n" "Phone Number\n\n\n" "DEFREZE, GREGORY\n" "10 BIG RIDGE RD, SPENCERPORT, NY 14559-1219.\n" "Phone Number 5853520978\n\n\n" "ENGLEHARDT, HERBERT\n" "75 TOTTENHAM RD, BRIGHTON, NY 14610-2244.\n" "Phone Number 585-482-2955\n\n\n" "CARTER, GARY\n" "204 PINE HILL RD, SPENCERPORT, NY 14559-1010.\n" "Phone Number (585)352-8826\n\n\n" "DEGEN, MARK\n" "27 COBRA DR, HENRIETTA, NY 14467-9512.\n" "Phone Number 585-321-3524\n\n\n" "DEGENNARO, VICTOR\n" "537 WASHINGTON ST, SPENCERPORT, NY 14559-9539.\n" "Phone Number +1 (585) 352-3824\n\n\n" "FRANCIS, THOMAS\n" "4812 LYELL RD, SPENCERPORT, NY 14559-2014.\n" "Phone Number 585-352-4758\n\n\n" "CARTER, LINDA\n" "50 JORDACHE LN, SPENCERPORT, NY 14559-2059.\n" "Phone Number 585-352-4913") matches = re.finditer(regex, test_str, re.MULTILINE) 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