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

const regex = /(\d{3})(\d{3})(\d{4})/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(\\d{3})(\\d{3})(\\d{4})', 'g') const str = `7809392938 4033420393 7808757619 7804627372 4033431930 7804401427 3065843029 3068734346 3065459158 4032513899 6138371733 6136396120 6133220669 6132832702 7056961818 8195233827 8195379506 8193710857 6044659476 5065360323 9025972293 9026675158 3064418455 7808952118 6134731171 4188779045 4186634875 4162860104 9056469563 6136344085 9054536644 5192827449 7053682779 7057521683 7054767377 7054971162 7057593131 8075472443 9054782200 4168386400 7053270706 7056896545 5197823445 5194557669 5195425944 5194262785 9057762200 8193369296 4509373605 5143860399 4503489425 4506781069 4182962342 8679207104 9059739040 7058474747 2505806048 2502180257 6042709933 4164348199 7057210639 7057349081 2504791217 3063733403 5065460100 7803973778 6049434754 9023544384 5068709204 4037196000 2508820609 2509611173 7095898574 3066915254 4183975361 9028375909 5199157304 4189483659 8196842529 5064507449 5063575494 5063672576 6048929667 3068915205 5066331384 2503655167 2502653235 2507529278 2506245540 2505674718 7097494516 7095767638 7098320809 9026792314 9026442913 9026442293 9028658567 9027369404 9027423186 9028933908 4035278016 4032265840 4033278207 3062492680 2042756980 2046385237 2043393316 4506470945 4187383045 2505372791 9026872112 5193744315 4165968575 4036523816 6137283666 2504447144 4187360000 4188150011 8676672570 4504784078 5194810153 7806251607 4186957692 4506494109 6132668702 2507663003 6049901059 6139302145 2507232093 5199423280 6134765593 5064595336 5193519378 2508301088 8196372035 9028753656 9059346500 8075770789 6477909063 6049465187 7056462443 2505922183 7782161820 5192653223 5063974955 7092564814 4033370181 8198773421 9023683266 4033908888 3066936127 5199416173 4167812753 8676687380 6048460630 6137964840 5193376209 2506355865 2508474469 7056626061 9053080060 9054597533 9057237320 7803324545 2505542598 9026388451 8193783753 2507632056 5067354659 2505542955 7059465040 2046873964 6042028854 2048425342 7097456052 7056925631 9025661497 4509331802 4035274710 5195833619 5144575112 6136344247 5192419733 9055716776 6134760233 2504266049 6477634195 5146070708 5067552960 3069809211 4503022369 7804543304 7804637212 4032088354 4032819500 8673349753 8679207515 2507835562 4037586887 2508252215 7092273714 4186724195 6134157330 9052784681 4508354914 6047323899 8076226386 7807157130 5068588300 6133899546 4035273688 6042234345 2504931671 8198408405 2506890329 2507218688 6045911825 6044698609 3069241004 9055502464 4507772134 4166881095 5194733618 7057495520 9053324976 6042715299 6048856208 2503378239 2502454938 2506275956 5066331384 7053601885 6043392005 6472959264 4508186798 5146953528 2508324265 8079372062 8198555822 6136322153 2894311030 6049850214 9024364910 9028364364 2504422663 7059421737 9052799187 9057360310 4037586427 4183000661 9028257522 5144819024 4509644266 4039020100 3066347693 7053350460 5068321992 7057439571 7804674856 6138974467 5146298848 8677664124 5067399737 9028636932 7787824971 6042506974 5199698893 2508608660 5197370274 6042001562 6472004306 4167595783 3067782686 7804678679 6472338817 7057457119 7808122731 2507543528 4504717099 6135307723 4507993777 8195646350 7804794690 5197437840 4505300810 5196335949 4502248479 9023964040 4168547404 4033806498 2044779125 9025821561 9024662124 9024044215 7054812054 7097486282 6042437418 5064723929 5064548676 5064585957 5146884163 7059875411 7808269012 3066523701 7097271098 6134537921 2507684212 8192229743 4189624834 2509270781 4185628441 5194897027 7806675393 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions