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

re = /([\w-]+[_][\w-]*)/m str = '904-555-1212_Ramada-Holiday-opt2 foo ABC_TEMP_11_2011_09-02_9045551234-opt2 foo foo abc_TEMP_11_2011_09-02_9045551234 foo foo 904-900-2197_9045551212 foo foo FooBar_AL_2055551212 foo foo 904-555-1212_9045551212 foo Maintenance Notification 7725551212 Phone FooBaz_at_St_Lucie_West_FL_7725551212 liveCallback 1@FooFoo_at_Summerwood_TX_2814581010|sg(14) users/Jacksonville_FL/MG|m Office Notification 5105551212 Phone Los_Angeles_CA Maintenance LogIn Courtesy Transfer 8665551212 SIP/trunk_2_abc/18669302777 1@Popes_Hat_NC_7045551212|sg(14) users/Frogs_Feet_Washington_DC_2025551212/MG|m users/Mt_Food_Portland_OR_5035551212/INTRO|m SIP/trunk_2_icc/18669302777 3@Jelly_Bean_NC_8285551212|sg(14) ' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html