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

Substitution

Processing...

Code Generator

Language

Generated Code

re = /( \d{1,2})5(\d{2} )/ str = 'part1.htm">MiniTOC</a><a class="toc1" part2.htm">2/5/18, 4549 PM part3.htm">2/7/18, 4516 PM part4.htm">2/15/18, 2557 PM part5.htm">2/20/18, 2507 PM part6.htm">2/21/18, 3502 PM part7.htm">2/21/18, 5506 PM part8.htm">2/22/18, 10503 AM part9.htm">2/22/18, 1543 PM part10.htm">2/27/18, 3514 PM part11.htm">2/28/18, 2533 PM part12.htm">3/1/18, 1515 PM part13.htm">3/1/18, 2527 PM part14.htm">3/1/18, 6547 PM part15.htm">3/1/18, 8557 PM part16.htm">3/4/18, 11540 AM part17.htm">3/5/18, 4546 PM part18.htm">3/6/18, 12548 PM part19.htm">3/6/18, 2518 PM part20.htm">3/7/18, 12535 PM part21.htm">3/8/18, 8500 AM part22.htm">3/8/18, 10521 AM part23.htm">3/8/18, 12559 PM part24.htm">3/9/18, 10540 AM part25.htm">3/9/18, 1501 PM part26.htm">3/9/18, 6514 PM part27.htm">3/12/18, 8514 PM part28.htm">3/14/18, 12520 PM part29.htm">3/14/18, 2537 PM part30.htm">3/15/18, 2514 PM part31.htm">3/15/18, 3549 PM part32.htm">3/21/18, 11506 AM part33.htm">3/22/18, 2518 PM part34.htm">3/22/18, 3523 PM part35.htm">3/22/18, 4554 PM part36.htm">3/26/18, 3543 PM part37.htm">4/2/18, 1555 PM part38.htm">4/2/18, 4532 PM part39.htm">4/5/18, 1557 PM part40.htm">4/6/18, 4536 PM part41.htm">4/6/18, 5540 PM part42.htm">4/6/18, 7501 PM part43.htm">4/7/18, 5524 AM part44.htm">4/16/18, 12525 PM part45.htm">4/17/18, 4502 PM part46.htm">4/23/18, 7520 PM part47.htm">4/25/18, 3527 PM part48.htm">4/25/18, 5513 PM part49.htm">4/26/18, 2534 PM part50.htm">4/26/18, 6513 PM part51.htm">5/1/18, 3523 PM part52.htm">5/3/18, 3540 PM part53.htm">5/4/18, 12539 PM part54.htm">5/8/18, 12539 PM part55.htm">5/8/18, 2549 PM part56.htm">5/9/18, 12506 PM part57.htm">5/15/18, 3525 PM part58.htm">5/23/18, 6545 PM part59.htm">5/24/18, 2559 PM part60.htm">5/24/18, 5523 PM part61.htm">5/26/18, 3509 PM part62.htm">5/27/18, 11519 AM part63.htm">5/30/18, 4554 PM part64.htm">5/26/18, 1507 PM part65.htm">5/31/18, 2558 PM part66.htm">6/7/18, 2546 PM part67.htm">6/11/18, 7531 PM part68.htm">6/12/18, 10547 AM part69.htm">6/12/18, 3529 PM part70.htm">6/13/18, 7536 PM part71.htm">6/14/18, 3527 PM part72.htm">6/19/18, 8507 AM part73.htm">6/19/18, 3528 PM part74.htm">6/19/18, 5519 PM part75.htm">6/20/18, 10507 AM part76.htm">6/21/18, 10545 AM part77.htm">6/21/18, 12544 PM part78.htm">6/21/18, 3534 PM part79.htm">6/23/18, 11506 AM part80.htm">6/23/18, 3505 PM part81.htm">6/23/18, 6500 PM part82.htm">6/24/18, 10535 AM part83.htm">6/24/18, 12556 PM part84.htm">6/25/18, 7517 PM part85.htm">6/26/18, 3517 PM part86.htm">6/26/18, 4559 PM part87.htm">6/27/18, 9551 AM </a><a class="toc1" part88.htm">6/27/18, 11532 AM part89.htm">6/28/18, 4515 PM </a><a class="toc1" part90.htm">7/2/18, 6529 PM part91.htm">7/3/18, 3554 PM part92.htm">7/3/18, 5545 PM part93.htm">7/3/18, 7556 PM part94.htm">7/3/18, 9503 PM part95.htm">7/7/18, 5531 PM part96.htm">7/9/18, 4553 PM part97.htm">7/10/18, 8554 AM part98.htm">7/10/18, 5516 PM part99.htm">7/11/18, 11531 AM part100.htm">7/11/18, 3550 PM part101.htm">7/12/18, 4549 PM part102.htm">7/15/18, 3524 PM part103.htm">7/16/18, 10525 AM part104.htm">7/16/18, 11534 AM part105.htm">7/16/18, 6544 PM part106.htm">7/18/18, 11505 AM part107.htm">7/19/18, 1537 PM part108.htm">7/19/18, 3532 PM part109.htm">7/24/18, 10500 AM part110.htm">7/24/18, 2514 PM part111.htm">7/24/18, 3555 PM part112.htm">7/24/18, 7506 PM part113.htm">8/9/18, 12537 PM part114.htm">8/13/18, 3531 PM part115.htm">8/13/18, 5551 PM part116.htm">8/14/18, 12509 PM part117.htm">8/14/18, 1532 PM part118.htm">8/14/18, 3539 PM part119.htm">8/16/18, 4548 PM part120.htm">8/16/18, 4548 PM part121.htm">8/21/18, 6509 PM part122.htm">8/23/18, 11557 AM part123.htm">8/28/18, 4537 PM part124.htm">8/30/18, 7528 PM part125.htm">8/30/18, 10500 PM part126.htm">9/4/18, 2538 PM part127.htm">9/4/18, 5515 PM part128.htm">9/5/18, 3538 PM part129.htm">9/7/18, 5519 PM part130.htm">9/10/18, 3518 PM part131.htm">9/13/18, 8541 AM part132.htm">9/13/18, 11512 AM part133.htm">9/13/18, 12551 PM part134.htm">9/17/18, 6502 PM part135.htm">9/18/18, 3555 PM part136.htm">9/19/18, 9506 PM part137.htm">9/19/18, 11504 PM part138.htm">9/20/18, 12531 PM part139.htm">9/24/18, 4502 PM part140.htm">9/24/18, 6518 PM part141.htm">9/25/18, 9550 AM part142.htm">9/25/18, 5512 PM part143.htm">9/26/18, 12549 PM part144.htm">9/26/18, 6533 PM part145.htm">9/28/18, 9543 AM part146.htm">10/1/18, 7558 AM part147.htm">10/1/18, 3538 PM part148.htm">10/3/18, 10551 AM part149.htm">10/3/18, 3521 PM part150.htm">10/3/18, 4528 PM part151.htm">10/3/18, 5529 PM part152.htm">10/8/18, 11521 AM part153.htm">10/8/18, 2526 PM part154.htm">10/8/18, 4538 PM part155.htm">10/9/18, 1504 PM part156.htm">10/9/18, 4529 PM part157.htm">10/9/18, 6552 PM part158.htm">10/10/18, 6509 PM part159.htm">10/11/18, 1544 PM part160.htm">10/11/18, 3527 PM part161.htm">10/11/18, 5552 PM part162.htm">10/11/18, 8500 PM part163.htm">10/16/18, 2515 PM part164.htm">10/16/18, 4501 PM part165.htm">10/18/18, 10541 AM part166.htm">10/18/18, 1505 PM part167.htm">10/18/18, 4524 PM part168.htm">10/18/18, 7537 PM part169.htm">10/19/18, 11532 AM part170.htm">10/22/18, 9539 AM part171.htm">10/22/18, 10543 AM part172.htm">10/22/18, 12514 PM part173.htm">10/22/18, 2523 PM part174.htm">10/24/18, 10506 AM part175.htm">10/24/18, 12535 PM part176.htm">10/24/18, 5558 PM part177.htm">11/1/18, 3525 PM part178.htm">11/1/18, 3525 PM part179.htm">11/5/18, 11509 AM part180.htm">11/5/18, 1544 PM part181.htm">11/8/18, 6521 PM part182.htm">11/9/18, 11538 AM part183.htm">11/10/18, 11525 AM part184.htm">11/10/18, 2531 PM part185.htm">11/14/18, 10530 AM part186.htm">11/14/18, 2505 PM part187.htm">11/14/18, 4521 PM part188.htm">11/14/18, 5527 PM part189.htm">11/15/18, 11541 AM part190.htm">11/15/18, 12558 PM part191.htm">11/18/18, 8559 PM part192.htm">11/19/18, 11502 AM part193.htm">11/19/18, 12512 PM part194.htm">11/26/18, 12537 PM part195.htm"> 11/27/18, 3535 PM part196.htm">11/28/18, 9535 AM part197.htm">11/28/18, 12551 PM part198.htm">11/29/18, 11541 AM part199.htm">12/3/18, 11512 AM part200.htm">12/3/18, 4501 PM part201.htm">12/4/18, 12510 PM part202.htm">12/4/18, 2504 PM part203.htm">12/4/18, 3559 PM part204.htm">12/7/18, 11548 AM part205.htm">12/7/18, 1542 PM part206.htm">12/10/18, 12521 PM part207.htm">12/11/18, 12518 PM part208.htm">12/14/18, 9517 AM part209.htm">12/14/18, 11554 AM part210.htm">12/14/18, 1547 PM part211.htm">12/14/18, 3530 PM part212.htm">12/14/18, 9531 PM part213.htm">12/16/18, 6506 PM part214.htm">12/17/18, 11556 AM part215.htm">12/19/18, 4500 PM part216.htm">12/20/18, 2558 PM part217.htm">12/20/18, 7516 PM part218.htm">12/21/18, 4516 PM part219.htm">12/21/18, 7510 PM part220.htm">12/25/18, 10518 PM part221.htm">1/1/19, 10540 AM part222.htm">1/1/19, 3521 PM part223.htm">1/3/19, 6501 PM part224.htm">1/4/19, 11540 AM part225.htm">1/4/19, 2501 PM part226.htm">1/4/19, 3555 PM part227.htm">1/6/19, 2519 PM part228.htm">1/7/19, 9531 AM part229.htm">1/7/19, 11527 AM part230.htm">1/7/19, 9532 PM part231.htm">1/8/19, 10534 PM part232.htm">1/9/19, 1512 PM part233.htm">1/10/19, 9551 AM part234.htm">1/10/19, 5537 PM part235.htm">1/11/19, 12526 PM part236.htm">1/14/19, 12522 PM part237.htm">1/13/19, 6555 PM part238.htm">1/11/19, 1557 PM part239.htm">1/17/19, 9539 AM part240.htm">1/17/19, 3513 PM part241.htm">1/18/19, 1505 PM part242.htm">1/18/19, 2549 PM part243.htm">1/22/19, 9557 AM part244.htm">1/22/19, 3530 PM part245.htm">1/24/19, 12532 PM part246.htm">1/24/19, 2554 PM part247.htm">1/25/19, 2554 PM part248.htm">1/29/19, 9552 AM part249.htm">1/30/19, 8528 AM part250.htm">1/30/19, 11550 AM part251.htm">2/1/19, 9506 AM part252.htm">2/1/19, 11529 AM part253.htm">2/1/19, 12557 PM part254.htm">2/1/19, 4522 PM part255.htm">2/2/19, 8519 AM part256.htm">2/5/19, 1500 PM part257.htm">2/5/19, 3537 PM part258.htm">2/7/19, 2534 PM part259.htm">2/8/19, 3526 PM part260.htm">2/8/19, 5510 PM part261.htm">2/11/19, 4538 PM part262.htm">2/12/19, 10555 AM part263.htm">2/13/19, 2514 PM part264.htm">2/13/19, 4533 PM part265.htm">2/13/19, 8537 PM part266.htm">2/14/19, 8544 AM part267.htm">2/14/19, 10516 AM part268.htm">2/14/19, 11543 AM part269.htm">2/16/19, 2501 PM part270.htm">2/16/19, 3541 PM part271.htm">2/19/19, 7501 PM part272.htm">2/20/19, 10526 AM part273.htm">2/20/19, 12501 PM part274.htm">2/20/19, 4534 PM part275.htm">2/24/19, 10550 AM part276.htm">2/24/19, 12506 PM part277.htm">2/24/19, 12506 PM part278.htm">2/25/19, 1541 PM part279.htm">2/25/19, 4554 PM part280.htm">2/28/19, 2522 PM part281.htm">3/6/19, 12522 PM part282.htm">3/7/19, 12522 PM part283.htm">3/7/19, 4517 PM part284.htm">3/8/19, 2534 PM part285.htm">3/12/19, 7514 PM part286.htm">3/13/19, 11546 AM part287.htm">3/13/19, 12552 PM part288.htm">3/14/19, 2502 PM part289.htm">3/15/19, 12545 PM part290.htm">3/15/19, 4553 PM part291.htm">3/18/19, 10522 AM part292.htm">3/18/19, 11544 AM part293.htm">3/18/19, 2536 PM part294.htm">3/18/19, 4513 PM part295.htm">3/19/19, 10506 AM part296.htm">3/19/19, 1543 PM part297.htm">3/20/19, 10530 AM part298.htm">3/24/19, 11516 AM part299.htm">3/24/19, 1533 PM part300.htm">3/26/19, 8530 AM part301.htm">3/28/19, 9507 PM part302.htm">3/29/19, 8523 AM part303.htm">4/2/19, 10504 AM part304.htm">4/2/19, 11534 AM part305.htm">4/2/19, 1508 PM ' subst = '\\1:\\2' 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