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

/
/
gmi

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mi)^[\s\u00A9\u00AE\u203C\u2049\u2122\u2139\u2194-\u2199\u21A9-\u21AA\u231A-\u231B\u2328\u23CF\u23E9-\u23F3\u23F8-\u23FA\u24C2\u25AA-\u25AB\u25B6\u25C0\u25FB-\u25FE\u2600-\u2604\u260E\u2611\u2614-\u2615\u2618\u261D\u2620\u2622-\u2623\u2626\u262A\u262E-\u262F\u2638-\u263A\u2648-\u2653\u2660\u2663\u2665-\u2666\u2668\u267B\u267F\u2692-\u2694\u2696-\u2697\u2699\u269B-\u269C\u26A0-\u26A1\u26AA-\u26AB\u26B0-\u26B1\u26BD-\u26BE\u26C4-\u26C5\u26C8\u26CE-\u26CF\u26D1\u26D3-\u26D4\u26E9-\u26EA\u26F0-\u26F5\u26F7-\u26FA\u26FD\u2702\u2705\u2708-\u270D\u270F\u2712\u2714\u2716\u271D\u2721\u2728\u2733-\u2734\u2744\u2747\u274C\u274E\u2753-\u2755\u2757\u2763-\u2764\u2795-\u2797\u27A1\u27B0\u27BF\u2934-\u2935\u2B05-\u2B07\u2B1B-\u2B1C\u2B50\u2B55\u3030\u303D\u3297\u3299\u1F004\u1F0CF\u1F170-\u1F171\u1F17E-\u1F17F\u1F18E\u1F191-\u1F19A\u1F201-\u1F202\u1F21A\u1F22F\u1F232-\u1F23A\u1F250-\u1F251\u1F300-\u1F321\u1F324-\u1F393\u1F396-\u1F397\u1F399-\u1F39B\u1F39E-\u1F3F0\u1F3F3-\u1F3F5\u1F3F7-\u1F4FD\u1F4FF-\u1F53D\u1F549-\u1F54E\u1F550-\u1F567\u1F56F-\u1F570\u1F573-\u1F579\u1F587\u1F58A-\u1F58D\u1F590\u1F595-\u1F596\u1F5A5\u1F5A8\u1F5B1-\u1F5B2\u1F5BC\u1F5C2-\u1F5C4\u1F5D1-\u1F5D3\u1F5DC-\u1F5DE\u1F5E1\u1F5E3\u1F5EF\u1F5F3\u1F5FA-\u1F64F\u1F680-\u1F6C5\u1F6CB-\u1F6D0\u1F6E0-\u1F6E5\u1F6E9\u1F6EB-\u1F6EC\u1F6F0\u1F6F3\u1F910-\u1F918\u1F980-\u1F984\u1F9C0}]+$`) var str = `Test with Unicode עברית Test with Unicode and Emoji ? עברית ` 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/