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Data & Formatting · In-Browser Regular Expression Lab

URL Slug Regex — Clean Kebab-Case Web Permalinks

Matches lowercase alphanumeric strings separated by single hyphens, ideal for SEO permalinks.

Flags:
//none
Match Found
Load Sample:
Match Inspection & Details1 match
Match #1:nextjs-developer-guide

Test Samples Verification Matrix

Expected Valid Samples (Should Match)

nextjs-developer-guide Pass
regex-101-cheat-sheet Pass
fast-api Pass

Expected Invalid Samples (Must Reject)

-leading-dash Rejected (Pass)
trailing-dash- Rejected (Pass)
double--hyphen Rejected (Pass)
Upper-Case Rejected (Pass)
Code Implementation Generator
// JavaScript / TypeScript (ES6+)
const pattern = /^[a-z0-9]+(?:-[a-z0-9]+)*$/;
const text = "nextjs-developer-guide";

const isMatch = pattern.test(text);
console.log("Is Match:", isMatch);

if (isMatch) {
  const matches = text.match(pattern);
  console.log("Matches:", matches);
}

Regular Expression Token Breakdown

Enforces strictly lowercase letters and digits separated by hyphens without leading, trailing, or double dashes. Each component of the regular expression serves a distinct syntactical purpose as mapped below:

Token PatternName / ComponentFunction & Rule
^[a-z0-9]+Initial WordMust begin with alphanumeric chars.
(?:-[a-z0-9]+)*$Hyphenated WordsRepeats a single hyphen followed by more alphanumeric chars.

Frequently Asked Questions

Can slugs contain underscores?
To permit underscores, use `^[a-z0-9]+(?:[-_][a-z0-9]+)*$`.

Related Regular Expressions

Browse All 40 Patterns
Network & Web

HTTP & HTTPS URL Validation

Matches fully qualified URLs starting with http:// or https://, including subdomains, paths, ports, and query parameters.

/^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}(?:\.[a-zA-Z0-9()]{1,6})?(?::[0-9]{1,5})?\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/i
Test regex
Authentication & Security

Alphanumeric Username

Standard web application username policy: 3 to 20 characters, starting with a letter, allowing underscores.

/^[a-zA-Z][a-zA-Z0-9_]{2,19}$/
Test regex
Code & Markup

Semantic Version (SemVer 2.0)

Full SemVer 2.0.0 specification regex validating major, minor, patch, and optional pre-release/build tags.

/^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$/
Test regex