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"
"
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression. sed -E 's/^(?P<Username>[-\w\.]+)(?:\s+\W*at\W*\s+|\s*[^\@\s]*?@[^\@\s]*?\s*)(?P<Domain>([\w\-]+)(?:(?:\.|\s+\W*?dot\W*?\s+)([\w\-]+))+?(?:(?:\.|\s+\W*?dot\W*?\s+)([\w\-]+))??$)/\1@\3.\4/gm;t' <<< "Parse email, also distorted ones, and convert them back to the real ones. Inspirated by dislick's work: https://regex101.com/r/wB7xJ7/1 frenci98@gmail.com st11389@copernico.bo.it gigilafontana .at. gmail [dot] com d98.copernico@gmail.com domenico-tosello at dotcom-sas dot com my.e-M4il [at] w3-spAce.org email@sub-sub.sub dot domain dot info email@foo dot foo dot foo dot foo"

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 SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html