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

/
/

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(\{.*\})`) var str = `Email Newsletter@media only screen and (max-width: 415px) {table[class=\"main-table\"],table[class=\"main-table\"] .image {width: 100% !important;}table[class=\"main-table\"] .image {max-width:100% !important;height:auto !important;}table[class=\"main-table\"] .row {display:block !important;width:100% !important;margin-bottom:20px !important;}table[class=\"main-table\"] .row .separator {width:20px !important;}table[class=\"main-table\"] .mobile {display: none !important;}table[class=\"main-table\"] .block{display: block !important;}table[class=\"main-table\"] .top-menu{width: 25% !important;}}Thank you for considering the Acura RDX. Check out the latest videos, features, and details from the Acura RDX below.VIEW IN BROWSERNew InventoryCertified Pre-Owned InventoryLease & FinanceHelloThank you for considering the Acura RDX. Check out the latest videos, features, and details from the Acura RDX below.TRIMS & COLORSPHOTO GALLERY360° TOURVIDEOSFEATURESSPECIFICATIONSCOMPETITIVE COMPARISONBUILD AND PRICERDXStarting at $35,270MSRP includes destination and handling279-hp, 3.5-liter, i-VTEC® V-66-spd. Sequential SportShift paddle shiftersFront-wheel driveJewel Eye® LED headlightsRDX with Technology and AcuraWatch Plus PackagesStarting at$40,270MSRP includes destination and handlingCollision Mitigation Braking System™ (CMBS™)Lane Keeping Assist System (LKAS)59Color Multi-information display (MID)Adaptive Cruise Control (ACC)53RDX AWD with Advance PackageStarting at $43,420MSRP includes destination and handlingAWD with Intelligent Control System™9655 SW Canyon RoadPortland, OR97225SALES (866) 985-5966SERVICE (866) 980-4615PARTS (877) 245-7434MSRP includes destination and handlingTO OPT-DOWN OR UNSUBSCRIBE: This e-mail was sent to you because you area valued Ron Tonkin Acura customer. To receive fewer updates or removeyourself from our e-mail program, please unsubscribe.` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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/