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

/
/
g

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`\{\\rtf1\\ansi\\ansicpg1252(?:.|[\r\n]+)*\{\\\*\\listtable`) var str = `{\rtf1\ansi\ansicpg1252 \deff0{\fonttbl{\f0\froman\fcharset0 Times New Roman;}{\f1\froman\fcharset0 HELVETICA;}{\f2\froman\fcharset0 Arial;}{\f3\froman\fcharset0 unknown;}{\f4\froman\fcharset0 HELVETICA-BOLD;}{\f5\froman\fcharset0 Helvetica;}} {\colortbl\red0\green0\blue0;\red255\green255\blue255;\red244\green245\blue255;\red254\green182\blue230;\red0\green0\blue255;} {\stylesheet {\style\s0 \ql\fi0\li0\ri0\f2\fs24\cf0 Normal;} {\style\s3 \ql\fi0\li0\ri0\f2\fs26\b\cf0 heading 3;} {\style\s2 \ql\fi0\li0\ri0\f2\fs28\b\i\cf0 heading 2;} {\style\s1 \ql\fi0\li0\ri0\f2\fs32\b\cf0 heading 1;} } {\*\listtable {\style\s0 \ql\fi0\li0\ri0\f2\fs24\cf0 Normal;} {\style\s3 \ql\fi0\li0\ri0\f2\fs26\b\cf0 heading 3;} {\style\s2 \ql\fi0\li0\ri0\f2\fs28\b\i\cf0 heading 2;} {\style\s1 \ql\fi0\li0\ri0\f2\fs32\b\cf0 heading 1;} } {\*\listtable } {\*\listoverridetable } {\*\generator iText 2.1.2 (by lowagie.com)} {\info}` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/