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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?i)^\s*(.*((p|post)[-.\s]*(o|off|office)[-.\s]*(b|box|bin)[-.\s]*)|.*((p|post)[-.\s]*(o|off|office)[-.\s]*)|.*((p|post)[-.\s]*(b|box|bin)[-.\s]*)|(box|bin)[-.\s]*)(#|n|num|number)?\s*\d+", flags=re.MULTILINE) test_str = ("-- Match\n" "post office box 1\n" "post office bin 1\n" "post office b 1\n" "post off box 1\n" "post off bin 1\n" "post off b 1\n" "post o box 1\n" "post o bin 1\n" "post o b 1\n" "p office box 1\n" "p office bin 1\n" "p office b 1\n" "p off box 1\n" "p off bin 1\n" "p off b 1\n" "p o box 1\n" "p o bin 1\n" "p o b 1\n" "p-o-b-1\n" "p.o.b.1\n" "POB1\n" "pob1\n" "pob#1\n" "pob #1\n" "pob # 1\n" " p o b # 1 x\n" " p o b # 1 x\n" "pob n1\n" "pob num1\n" "pob number1\n" "foo pob1\n" "1 pob1\n" "box 1\n" "bin 1\n" "box-1\n" "box.1\n" "box1\n" "BOX1\n" "box#1\n" "box #1\n" "box # 1\n" " box # 1 x\n" " box # 1 x\n" "po 1\n" "po n1\n" "PO 1\n" "pb 1\n" "pb n1\n" "PB 1\n\n" "-- No Match\n" "foo box 1\n" "b1\n" "#1\n" "1 box 1\n" "1 pob\n" "post 1\n" "n1\n" "number1\n" "num1\n" "post office box\n" "post office bin\n" "post office b\n" "post off box\n" "post off bin\n" "post off b\n" "post o box\n" "post o bin\n" "post o b\n" "p office box\n" "p office bin\n" "p office b\n" "p off box\n" "p off bin\n" "p off b\n" "p o box\n" "p o bin\n" "p o b\n" "p-o-b-\n" "p.o.b.\n" "POB\n" "pob\n" "pob#\n" "pob #\n" "pob #\n" " p o b # x\n" " p o b # x\n" "pob n\n" "pob num\n" "pob number\n" "foo pob\n" "box\n" "bin \n" "box-\n" "box.\n" "box\n" "BOX\n" "box#\n" "box #\n" "box # \n" " box # x\n" " box # x\n" "po\n" "po n\n" "PO\n" "pb\n" "pb n\n" "PB") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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