Regex for Domain Name

Validates domain names with proper label format and TLD.

Pattern

/^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$/i

Live Tester

Enter a string to test

Examples

The i flag makes the pattern case-insensitive.

✓ example.com

✓ sub.domain.co.uk

✓ my-site.org

✗ -example.com

✗ example-.com

✗ .com

Pattern Breakdown

([a-zA-Z0-9]...) — label starts/ends with alphanumeric

\. — dot separator

+ — one or more labels

[a-zA-Z]{2,}$ — TLD of 2+ letters

Code Snippets

Javascript

/^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$/i.test("example.com"); // true

Python

bool(re.match(r"^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$", "example.com", re.I))  # True

Php

preg_match('/^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$/i', "example.com"); // 1

Related Patterns

Email Address /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/ URL /^https?:\/\/(www\.)?[a-zA-Z0-9@:%._+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([a-zA-Z0-9()@:%_+.~#?&/=-]*)$/ Phone Number (International) /^\+?[1-9]\d{1,14}$/ Phone Number (US) /^$?[2-9]\d{2}$?[-.\s]?\d{3}[-.\s]?\d{4}$/ Phone Number (EU) /^\+?[1-9][0-9]{0,3}[\s.-]?$?[0-9]{1,5}$?[\s.-]?[0-9]{1,5}[\s.-]?[0-9]{1,5}$/ IPv4 Address /^((25[0-5]|2[0-4]\d|[01]?\d\d?)\.){3}(25[0-5]|2[0-4]\d|[01]?\d\d?)$/

Frequently Asked Questions

What is the regex for Domain Name?▾

The regex pattern for Domain Name is /^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$/i. Validates domain names with proper label format and TLD.

How do I use the Domain Name regex in JavaScript?▾

In JavaScript you create the pattern with a regex literal or the RegExp constructor and call .test() to check a string against it. A ready-to-copy example is shown in the Code Snippets section above, alongside Python and PHP versions.

What does the Domain Name pattern match?▾

It matches strings like example.com; it rejects strings like -example.com. See the Examples section above for the full list of matching and non-matching cases.