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

/
/
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/(\s)(C\d+)(\s)/\2\3/gm;t' <<< "✓ C3563118 - when the Analytics page is displayed AND advertising content is NOT available, the Analytics window displays at full width (11165ms) ✓ When mark down is selected, include zero is disabled (12421ms) ✓ include zero selection resets after clicking mark down (2991ms) ✓ C3563119 - when the Analytics page is displayed AND advertising content IS available, an advertising image is displayed to the left OR above the Looker dashboard content (based on screen size). (5536ms) ✓ C3563121 - when advertising content is displayed on the Analytics page, the content is responsive to screen size changes (5597ms) ✓ C3563122 - when advertising content is displayed on the Analytics page, the content is sourced from the correct environment (Prod/Non-Prod) (3083ms) C3563120 - when advertising content is displayed on the Analytics page, the content is associated to the Pricing/Product Tier of the users Organization ✓ Checks orgs with pricing tier Core, only see advertisements for that tier (5847ms)"

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