What is an example of a matching and non-matching string?

A valid matching string is "https://devtransform-hub.vercel.app/tools/". A non-matching string is "htp://invalid-url".

Is this regex safe from ReDoS (Catastrophic Backtracking)?

Yes, this pattern is optimized for linear execution time and safe for browser-side validation without locking up the UI thread.

HomeRegex LibraryHTTP/HTTPS URL Validation Regex

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HTTP/HTTPS URL Validation Regex

Q: How do I test this regex in JavaScript and TypeScript?

Use regex.test(): const regex = /^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/i; const isValid = regex.test(inputString);

Validates web URLs including domain, optional port, and query parameter path.

Regular Expression Pattern:

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

Valid Match Example:

https://devtransform-hub.vercel.app/tools/

Invalid / Non-Match Example:

htp://invalid-url

Regex Syntax Breakdown & Explanation

•^https?:\/\/ : Matches http or https protocol
•(?:www\.)? : Optional www prefix
•[-a-zA-Z0-9...]{1,256} : Domain name
•\.[a-zA-Z0-9()]{1,6} : Valid TLD extension

Implementation in Popular Languages

JavaScript / TypeScript

const regex = /^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/i;
const isValid = regex.test("https://devtransform-hub.vercel.app/tools/");
console.log(isValid); // true

Python (re)

import re

pattern = r"^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$"
match = re.match(pattern, "https://devtransform-hub.vercel.app/tools/")
print(bool(match)) # True

Go (regexp)

package main
import (
  "fmt"
  "regexp"
)

func main() {
  re := regexp.MustCompile(`^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$`)
  fmt.Println(re.MatchString("https://devtransform-hub.vercel.app/tools/"))
}

Frequently Asked Questions

Everything you need to know regarding specifications, syntax, and security best practices.

The regular expression pattern is /^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/i. Validates web URLs including domain, optional port, and query parameter path.