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Domain Name Validator

Validate domain name format per RFC 1035/5891, check label and total length, verify TLD, and detect IDN domains.

Enter a domain name above to validate

We'll check format, label lengths, TLD, and IDN detection

What we check

Format Check

Validating domain name format and character set

Label Length

Verifying each label is between 1 and 63 characters

Total Length

Checking total domain length is within 253 characters

TLD Validation

Verifying the top-level domain is valid

IDN Detection

Detecting internationalized domain name (punycode or non-ASCII)

Learn More

Domain Name Validator: Check DNS Naming Rules and TLD Types

Learn how domain name validation works, DNS naming rules, label constraints, and TLD types.

What Is a Domain Name?

A domain name is a human-readable address that maps to a numeric IP address on the internet. Instead of remembering 93.184.216.34, users can type example.com into their browser. The Domain Name System (DNS) translates these names into IP addresses behind the scenes.

5 min readRead full guide