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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
gmi

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/.(?=.{4})//gmi;t' <<< "usdfiusdgfisdgf LovePizza 12,34,56,78 12.34.56,78 Esto es una prueba hola 12345678 45345345343 Nananananananananananananananana Batman! nada@gmail.com lorena.loba@loquesea.gov.co hola_3@gmail.com adios@gmail.com pruebagmail.com pepe.trueno patricia99.rica@.hotmail.com lorena22.regalada comercio.enproceso daniela regalo gmail.com redluis.luis@gmail.com pepe_redluis@gmail.com pepe_redluis@gmail.com mart-red+luis@gmail.com.ve { \"servicio\":\"eval\", \"eval\":{ \"10441\":\"valor.%substr%( 2, 2 )\", \"10442\":\"valor\", \"10443\":\"%mask%(valor,3)\" }, \"operacion\":\"valor.%concat%(10442,10443,10441)\", \"resultado\":12022 } 1. Luciana: 4.216 2. Isabella: 3.505 3. Salomé: 2.829 4. Emmanuel: 2.688 5. Antonella: 2.643 6. Emiliano: 2454 7. Santiago: 2.383 8. Samuel: 2.256 9. Jerónimo: 2.167 10. Mariana: 2.160 date,home_team,away_team,home_score,away_score,tournament,city,country,neutral 1872-11-30,Scotland,England,0,0,Friendly,Glasgow,Scotland,FALSE 1873-03-08,England,Scotland,4,2,Friendly,London,England,FALSE 1874-03-07,Scotland,England,2,1,Friendly,Glasgow,Scotland,FALSE 1875-03-06,England,Scotland,2,2,Friendly,London,England,FALSE 1876-03-04,Scotland,England,3,0,Friendly,Glasgow,Scotland,FALSE 1876-03-25,Scotland,Wales,4,0,Friendly,Glasgow,Scotland,FALSE 1::Toy Story (1995)::Adventure|Animation|Children|Comedy|Fantasy 2::Jumanji (1995)::Adventure|Children|Fantasy 3::Grumpier Old Men (1995)::Comedy|Romance 4::Waiting to Exhale (1995)::Comedy|Drama|Romance 5::Father of the Bride Part II (1995)::Comedy 6::Heat (1995)::Action|Crime|Thriller 7::Sabrina (1995)::Comedy|Romance 8::Tom and Huck (1995)::Adventure|Children 9::Sudden Death (1995)::Action 10::GoldenEye (1995)::Action|Adventure|Thriller 11::American President, The (1995)::Comedy|Drama|Romance 12::Dracula: Dead and Loving It (1995)::Comedy|Horror 13::Balto (1995)::Animation|Children 14::Nixon (1995)::Drama 15::Cutthroat Island (1995)::Action|Adventure|Romance 16::Casino (1995)::Crime|Drama 17::Sense and Sensibility (1995)::Comedy|Drama|Romance 18::Four Rooms (1995)::Comedy|Drama|Thriller 19::Ace Ventura: When Nature Calls (1995)::Comedy 20::Money Train (1995)::Action|Comedy|Crime|Drama|Thriller"

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