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

r"
"
gmi

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('^\\s(\\w{1,}):\\s+((?:\\w\\w\\s)+)\\s+(\\w+)(.*)', 'gmi') const str = ` 6bb: c3 ret 6bc: 0f 1f 40 00 nop DWORD PTR [rax+0x0] 6c0: 41 57 push r15 6c2: 41 56 push r14 6c4: 41 89 ff mov r15d,edi 6c7: 41 55 push r13 6c9: 41 54 push r12 6cb: 4c 8d 25 06 07 20 00 lea r12,[rip+0x200706] # 0x200dd8 6d2: 55 push rbp 6d3: 48 8d 2d 06 07 20 00 lea rbp,[rip+0x200706] # 0x200de0 6da: 53 push rbx 6db: 49 89 f6 mov r14,rsi 6de: 49 89 d5 mov r13,rdx 6e1: 4c 29 e5 sub rbp,r12 6e4: 48 83 ec 08 sub rsp,0x8 6e8: 48 c1 fd 03 sar rbp,0x3 6ec: e8 3f fe ff ff call 0x530 6f1: 48 85 ed test rbp,rbp 6f4: 74 20 je 0x716 6f6: 31 db xor ebx,ebx 6f8: 0f 1f 84 00 00 00 00 nop DWORD PTR [rax+rax*1+0x0] 6ff: 00 700: 4c 89 ea mov rdx,r13 703: 4c 89 f6 mov rsi,r14 706: 44 89 ff mov edi,r15d 709: 41 ff 14 dc call QWORD PTR [r12+rbx*8] 70d: 48 83 c3 01 add rbx,0x1 711: 48 39 dd cmp rbp,rbx 714: 75 ea jne 0x700 716: 48 83 c4 08 add rsp,0x8 71a: 5b pop rbx 71b: 5d pop rbp 71c: 41 5c pop r12 71e: 41 5d pop r13 720: 41 5e pop r14 722: 41 5f pop r15 724: c3 ret 725: 90 nop 726: 66 2e 0f 1f 84 00 00 nop WORD PTR cs:[rax+rax*1+0x0] 72d: 00 00 00 730: f3 c3 repz ret `; // 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