Patterns for common data Updated November 2026

Regex for URL

A usable URL regex is ^https?:\/\/[^\s/$.?#][^\s]*$ : http or https, a host that does not start with a dot or slash, then anything except whitespace. To extract links from text use https?:\/\/[^\s<>]*[^\s<>.,;:] with the g flag. For strict validation in JavaScript, prefer new URL(string) inside a try block.

Syntax

/^https?:\/\/[^\s/$.?#][^\s]*$/

Examples

/^https?:\/\/[^\s/$.?#][^\s]*$/.test("https://example.com/path?q=1")

Result: true

/^https?:\/\/[^\s/$.?#][^\s]*$/.test("example.com")

Result: false

The scheme is required. Use (?:https?:\/\/)? to make it optional.

"See https://a.com/x and http://b.org.".match(/https?:\/\/[^\s<>]*[^\s<>.,;:]/g)

Result: ["https://a.com/x", "http://b.org"]

The last class excludes punctuation so the sentence period is not swallowed.

"https://example.com:8080/docs/intro?x=1".match(/^(https?):\/\/([^/:]+)(?::(\d+))?(\/[^?#]*)?/)

Result: ["https://example.com:8080/docs/intro", "https", "example.com", "8080", "/docs/intro"]

Groups: scheme, host, optional port, optional path.

Common mistakes

Unescaped slashes inside a JavaScript regex literal end the pattern early; write \/ or build the regex from a string.
Requiring www\. rejects most URLs; make it optional with (?:www\.)? or leave it out.
Capturing the trailing period or comma when extracting from prose; end the pattern with a class that excludes . , ; : and ).
Writing example.com without escaping the dot, which also matches examplexcom; escape literal dots as \.

Practice Regex for URL

These drills check your answer on live data, free, no account needed.

Host names from URLsFind the first http or https URL on the line and capture its host name in group 1: everything after :// up to a slash, colon, question mark, hash or whitespace.
URL slugsThe whole line must match. Match a URL slug: lowercase letters and digits in chunks joined by single hyphens. No hyphen at the start or end and no doubled hyphens.
Escaping: a price like $4.99The whole line must match. Match a dollar sign, one or more digits, a period and exactly two digits.

Questions

What is the regex for a URL without http?

Make the scheme optional: ^(?:https?:\/\/)?(?:www\.)?[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)+(?:\/\S*)?$ matches example.com, www.example.com/page and https://example.com.

How do I extract the domain from a URL with regex?

Use ^https?:\/\/([^/:?#]+) and read group 1, which gives example.com from https://example.com:8080/path. In JavaScript, new URL(u).hostname is simpler and handles edge cases.

Should I validate URLs with regex or new URL()?

Use new URL() for validation in JavaScript; it parses exactly what browsers accept. Use the regex when you need to find URLs inside text or when you work in a tool that only offers regex, such as a spreadsheet or SQL.

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