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

/
/
gm

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"First Name[\s\S](?<firstname>.*)[\s\S]Last Name[\s\S](?<lastname>.*)[\s\S]Phone[\s\S](?<phone>.*)[\s\S]E-Mail[\s\S](?<email>.*)[\s\S]*age group\?[\s\S](?<agegroup>.*)[\s\S]*seeing things up close[\s\S](?<farsightedness>.*)[\s\S]*cannot see very well[\s\S](?<astigmatism>.*)[\s\S]*-Glasses[\s\S](?<glasses>.*)[\s\S]*-Contacts[\s\S](?<contacts>.*)[\s\S]*-Reading Glasses[\s\S](?<readingglasses>.*)[\s\S]*following\?-(?<following>.*)[\s\S]*distance without relying on glasses and contact lenses.[\s\S](?<distance>.*)[\s\S]*close without relying on glasses and contact lenses.[\s\S](?<close>.*)[\s\S]*contacts\?[\s\S](?<wouldyourcareerimprove>.*)[\s\S]*Test Score[\s\S](?<testscore>.*)[\s\S]*Entry ID: (?<entryid>.*)[\s\S].*Referrer: (?<referrer>.*)[\s\S]*Host: (?<formhost>.*)" test_str = ("First Name Melissa\n" "Last Name Madrid\n" "Phone 4253068210\n" "E-Mail Meli.madrid@yahoo.com\n" "What is your age group? 19-39\n" "Without my glasses and contacts-Farsightedness : I have trouble reading and seeing things up close yes\n" "Without my glasses and contacts-Astigmatism : I have distorted vision and cannot see very well yes\n" "What do you usually wear?-Glasses yes\n" "What do you usually wear?-Contacts yes\n" "What do you usually wear?-Reading Glasses yes\n" "Do you have any of the following?-None of the above yes\n" "I would like to see well at a distance without relying on glasses and contact lenses. 5\n" "I would like to see well up close without relying on glasses and contact lenses. 5\n" "Would your career or business activities improve if you were to become less dependent on glasses and contacts? Yes\n" "Test Score -4.00\n\n" "The message has been sent from 107.77.205.32 (United States) at 2020-01-10 10:39:44 on iPhone unknown\n" "Entry ID: 2190\n" "Referrer: http://m.facebook.com\n" "Form Host: https://www.nweyes.com/landing/smile/") 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