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

/
/
g

Test String

Code Generator

Language

Generated Code

re = /([a-zA-Z ]+),/ str = 'California Alameda, CA Albany, CA Altadena, CA Alviso, CA Atherton, CA Belmont, CA Berkeley, CA Beverly Hills, CA Burbank, CA Burlingame, CA Campbell, CA Culver City, CA Cupertino, CA El Cerrito, CA Emeryville, CA Encino, CA Glendale, CA La Canada Flintridge, CA Los Altos, CA Los Angeles, CA Los Gatos, CA Marina Del Rey, CA Menlo Park, CA Millbrae, CA Mountain View, CA North Hollywood, CA Oakland, CA Pacific Palisades, CA Palo Alto, CA Pasadena, CA Playa Del Rey, CA Portola Valley, CA Redwood City, CA Reseda, CA San Bruno, CA San Carlos, CA San Francisco, CA San Jose, CA San Leandro, CA San Marino, CA San Mateo, CA Santa Clara, CA Santa Monica, CA Saratoga, CA Sherman Oaks, CA South Pasadena, CA South San Francisco, CA Stanford, CA Studio City, CA Sunnyvale, CA Tarzana, CA Valley Village, CA Van Nuys, CA Venice, CA West Hollywood, CA Colorado Boulder, CO Denver, CO Englewood, CO Lafayette, CO Louisville, CO Connecticut Canaan, CT East Canaan, CT Falls Village, CT Lakeville, CT Norfolk, CT Salisbury, CT Sharon, CT Stamford, CT West Cornwall, CT District of Columbia Washington, DC Florida Key Biscayne, FL Miami Beach, FL Miami, FL North Miami Beach, FL Georgia Alpharetta, GA Atlanta, GA Avondale Estates, GA Decatur, GA Marietta, GA Roswell, GA Scottdale, GA Smyrna, GA Illinois Aurora, IL Buffalo Grove, IL Chicago, IL Clarendon Hills, IL Deerfield, IL Downers Grove, IL Elmhurst, IL Evanston, IL Fort Sheridan, IL Glencoe, IL Glenview Nas, IL Glenview, IL Grayslake, IL Highland Park, IL Highwood, IL Hinsdale, IL Kenilworth, IL Lake Bluff, IL Lake Forest, IL Lake Zurich, IL Libertyville, IL Lincolnshire, IL Lincolnwood, IL Lisle, IL Mundelein, IL Naperville, IL Northbrook, IL Oak Brook, IL Prospect Heights, IL Skokie, IL Vernon Hills, IL Villa Park, IL Warrenville, IL Westmont, IL Wheeling, IL Wilmette, IL Winnetka, IL Indiana Carmel, IN Fishers, IN Indianapolis, IN Maryland Bethesda, MD Cabin John, MD Chevy Chase, MD Gaithersburg, MD Garrett Park, MD Kensington, MD Potomac, MD Rockville, MD Silver Spring, MD Takoma Park, MD Massachusetts Allston, MA Arlington, MA Ashley Falls, MA Auburndale, MA Babson Park, MA Belmont, MA Boston, MA Brighton, MA Brookline, MA Cambridge, MA Charlestown, MA Chestnut Hill, MA Jamaica Plain, MA Medford, MA Needham, MA New Town, MA Newton Center, MA Newton Highlands, MA Newton Lower Falls, MA Newton Upper Falls, MA Newton, MA Newtonville, MA Roslindale, MA Sheffield, MA Somerville, MA South Egremont, MA Waban, MA Waltham, MA Watertown, MA Wellesley Hills, MA Wellesley, MA West Newton, MA Michigan Ann Arbor, MI Birmingham, MI Bloomfield Hills, MI Chelsea, MI Commerce Township, MI Dexter, MI Farmington, MI Franklin, MI Keego Harbor, MI Novi, MI Plymouth, MI Rochester, MI Royal Oak, MI Saline, MI Southfield, MI Troy, MI Walled Lake, MI Waterford, MI West Bloomfield, MI Ypsilanti, MI Minnesota Hopkins, MN Minneapolis, MN Saint Paul, MN New Jersey Bloomfield, NJ Caldwell, NJ Cedar Grove, NJ Clifton, NJ Elmwood Park, NJ Fair Lawn, NJ Fairfield, NJ Garfield, NJ Haledon, NJ Lincoln Park, NJ Little Falls, NJ Montclair, NJ New York, NJ Nutley, NJ Passaic, NJ Paterson, NJ Pequannock, NJ Rutherford, NJ Saddle Brook, NJ Totowa, NJ Verona, NJ Wayne, NJ New York Amenia, NY Ancramdale, NY Arverne, NY Astoria, NY Bayside, NY Bellerose, NY Breezy Point, NY Brooklyn, NY Cambria Heights, NY College Point, NY Copake, NY Corona, NY East Elmhurst, NY Elmhurst, NY Far Rockaway, NY Flushing, NY Forest Hills, NY Fresh Meadows, NY Hollis, NY Howard Beach, NY Jackson Heights, NY Jamaica, NY Kew Gardens, NY Little Neck, NY Long Island City, NY Maspeth, NY Middle Village, NY Millerton, NY New York, NY Oakland Gardens, NY Ozone Park, NY Pine Plains, NY Queens Village, NY Rego Park, NY Richmond Hill, NY Ridgewood, NY Rockaway Park, NY Rosedale, NY Saint Albans, NY South Ozone Park, NY South Richmond Hill, NY Springfield Gardens, NY Sunnyside, NY Whitestone, NY Woodhaven, NY Woodside, NY Oregon Beaverton, OR Hillsboro, OR Lake Oswego, OR Portland, OR Tualatin, OR West Linn, OR Pennsylvania Abington, PA Ambler, PA Ardmore, PA Bala Cynwyd, PA Bensalem, PA Berwyn, PA Blue Bell, PA Bridgeport, PA Bryn Athyn, PA Bryn Mawr, PA Cheltenham, PA Collegeville, PA Conshohocken, PA Devon, PA Dresher, PA Drexel Hill, PA Elkins Park, PA Flourtown, PA Fort Washington, PA Gladwyne, PA Glenside, PA Gwynedd Valley, PA Gwynedd, PA Haverford, PA Havertown, PA Huntingdon Valley, PA Jenkintown, PA King Of Prussia, PA Lafayette Hill, PA Lansdale, PA Lansdowne, PA Malvern, PA Merion Station, PA Mont Clare, PA Montgomeryville, PA Narberth, PA Norristown, PA North Wales, PA Oreland, PA Paoli, PA Philadelphia, PA Phoenixville, PA Plymouth Meeting, PA Upper Darby, PA Villanova, PA Wayne, PA Willow Grove, PA Wyncote, PA Wynnewood, PA Texas Austin, TX Bellaire, TX Cedar Park, TX Conroe, TX Houston, TX Katy, TX Pflugerville, TX Round Rock, TX Sandy, TX Spring, TX Virginia Alexandria, VA Arlington, VA Dunn Loring, VA Falls Church, VA Ft Myer, VA McLean, VA Washington Bellevue, WA Kirkland, WA Lynnwood, WA Medina, WA Mercer Island, WA Mountlake Terrace, WA' # Print the match result str.scan(re) do |match| puts match.to_s end

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