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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)\"num_records\\":\s*(\d+)`) var str = `"{\"cursor\":\"\",\"hits\":3,\"results\":[{\"id\":65673,\"num_records\":14631,\"assets\":{\"ip_addresses\":14631,\"password\":14631,\"target_url\":14631,\"keyboard_languages\":14631,\"user_sys_registered_owner\":14484,\"country\":14631,\"infected_machine_id\":14631,\"email\":7346,\"username\":7285,\"user_os\":14631,\"user_hostname\":14631,\"log_id\":14631,\"infected_time\":14631,\"country_code\":14581}},{\"id\":65675,\"num_records\":2602,\"assets\":{\"display_resolution\":2602,\"ip_addresses\":2534,\"user_browser\":2602,\"password\":2602,\"target_url\":2602,\"keyboard_languages\":2602,\"user_sys_registered_owner\":2601,\"country\":2597,\"infected_machine_id\":2602,\"email\":943,\"full_name\":25,\"av_softwares\":2348,\"username\":1659,\"infected_path\":2534,\"user_os\":2602,\"log_id\":2602,\"infected_time\":2602,\"country_code\":2597,\"timezone\":2602}},{\"id\":65677,\"num_records\":139,\"assets\":{\"display_resolution\":139,\"ip_addresses\":139,\"user_browser\":139,\"password\":139,\"target_url\":139,\"keyboard_languages\":139,\"user_sys_registered_owner\":139,\"country\":139,\"infected_machine_id\":139,\"email\":3,\"full_name\":7,\"av_softwares\":139,\"username\":136,\"infected_path\":139,\"user_os\":139,\"log_id\":139,\"infected_time\":139,\"country_code\":139,\"timezone\":139}}]}" ` 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/