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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

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/<img src=([a-zA-Z0-9_\-\s\.\"=\\/:%,()]*class=\"[a-zA-Z0-9_\-\s\.\"=\\/:%,()]*lazy[a-zA-Z0-9_\-\s\.\"=\\/:%,()]*)/<img data-src=$1/gm;t' <<< " <img src=\"fonts/608be7747d9cf15397b0d112_Logo-v3-01.svg\" alt class=\"nav-logo\"> <img src=\"images/6085e0acf284d920e7133043_Frame%201%20%283%29.png\" loading=\"lazy\" width=\"500\" style=\"opacity:0\" srcset=\"images/6085e0acf284d920e7133043_Frame%201%20%283%29-p-500.png 500w, images/6085e0acf284d920e7133043_Frame%201%20%283%29.png 738w\" sizes=\"(max-width: 479px) 73vw, (max-width: 767px) 77vw, (max-width: 991px) 273.991455078125px, 380px\" alt class=\"image_header\"> <img src=\"images/6089c5d4b424624dc0cb450b_Frame%206.png\" loading=\"lazy\" width=\"263\" sizes=\"(max-width: 479px) 65vw, (max-width: 767px) 77vw, (max-width: 991px) 33vw, 37vw\" srcset=\"images/6089c5d4b424624dc0cb450b_Frame%206-p-500.png 500w, images/6089c5d4b424624dc0cb450b_Frame%206.png 651w\" alt class=\"image_performance lazy\"> <img src=\"images/6089c5d52359073cf4b6cc80_Frame%205.png\" loading=\"lazy\" width=\"287\" sizes=\"(max-width: 479px) 77vw, (max-width: 767px) 85vw, (max-width: 991px) 41vw, 43vw\" srcset=\"images/6089c5d52359073cf4b6cc80_Frame%205-p-500.png 500w, images/6089c5d52359073cf4b6cc80_Frame%205.png 771w\" alt class=\"image_security lazy\"> <img src=\"images/6089c5d4e99fbfce103ab502_Frame%207.png\" loading=\"lazy\" width=\"292\" sizes=\"(max-width: 479px) 71vw, (max-width: 767px) 81vw, (max-width: 991px) 263.991455078125px, 370px\" srcset=\"images/6089c5d4e99fbfce103ab502_Frame%207-p-500.png 500w, images/6089c5d4e99fbfce103ab502_Frame%207.png 651w\" alt class=\"image_reliability lazy\"> <img src=\"fonts/608be7747d9cf15397b0d112_Logo-v3-01.svg\" alt class=\"footer-logo-copy lazy\"> <img src=\"fonts/60857020dc3fb163eb8a7d19_icons8-instagram.svg\" loading=\"lazy\" alt class=\"instagram_logo lazy\">"

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