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

Code Generator

Language

Generated Code

const regex = new RegExp('^([a-zA-Z0-9-]{1,})>(.*?)[,](.*){1,},(qA[CXUoOSrRiZI]),(.+){1,}:', 'gm') const str = `# aprsc 2.1.13-g79b6c3e # logresp WV6L unverified, server FIRST KG6DMY-9>APAT51,RCHFLD,WIDE1*,qAR,ABAJO:!3846.80N/11205.07W&261/000/A=005347I'm Charles. 146.640 - pl 100 N3FAA>APRS,TCPIP*,qAC,AMBCWOP-2:@062011z3447.10N/11816.47W_049/001g002t053r000p001P001h57b10216L412AmbientCWOP.com KM6WSX>APX219,N6EX-4*,qAR,KELLER:=3405.98N/11736.25W-/A=001105/ K7EDT-S>APDG01,TCPIP*,qAC,K7EDT-GS:;K7EDT B *062011z3322.32ND11148.72WaRNG0001/A=000010 440 Voice 443.12500MHz +0.0000MHz RUTH>APNX02,WIDE3-3,qAR,N7GWT:!3918.75NS11505.39W#PHG58306/W3,NVn,N7GWT, Kimberly Pk, Nv KD6FEE>APFII0,qAC,APRSFI:@201141h3343.14N/11747.18W[178/000/A=000108Stormprobe | KD6FEE@arrl.net!w5X! XE2BNC-1>APMI06,WIDE2-2,qAR,XE2SI-10:@070122z3218.82N/11639.92WnPHG59304/CREBC Cerro Bola N4RDZ-9>S3SWXY,W7DXJ-12,WIDE1,W6SCE-11*,WIDE2,qAR,N2GTR-2:\`*)p{k>/\`"7/}_% SQUAW>APN391,qAO,PVALY:!3428.16NS11152.56W#PHG3000/W3,AZn SQUAW PEAK DIGI 6479 FT W7EI W7JLW>APRS,TCPIP*,qAC,T2CSNGRAD:@062013z3240.80N/11425.20W_049/003g007t062r000p000P000h44b10221eCumulusDsVP K6CMG-7>APDR16,TCPIP*,qAC,T2FINLAND:=3404.28N/11728.09Wu359/002/A=000973 up to no good. KC6JPG-D>APDG03,TCPIP*,qAC,KC6JPG-DS:!3407.92ND11733.37W&/A=000000440 MMDVM Voice 426.50000MHz +0.0000MHz, APRS for DMRGateway KG5SWO>APRS,TCPIP*,qAC,AMBCWOP-2:@062011z3803.83N/12039.19W_151/000g000t054r000p000P000h60b10251L264AmbientCWOP.com K0RNA-9>S3TVSQ,WIDE1-1,WIDE2-1,qAR,AG7GK-2:\`(0Vm-6k/\`"8p}Encore Floors -Blue F-150 - Rich-Love,Peace,& Chicken Grease_% KG6DMY-9>APAT51,RCHFLD,BACON,WIDE1*,qAR,ABAJO:!3846.80N/11205.07W&261/000/A=005347I'm Charles. 146.640 - pl 100 `; // 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