Validators

Domain Validator

Check if a domain name is in valid format and with accepted TLD.

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How to use

  1. 1Paste the domain.
  2. 2Click Process.
  3. 3See if it is valid and has an accepted TLD.

About

Checks the format of domain names and whether the TLD is valid. Handy for registering and validating sites.

How to validate a domain correctly

The domain validator checks whether a name follows DNS rules, verifying labels, TLD, and allowed characters. It is useful for reviewing domains before registration, in forms, and in service configurations.

A domain is divided into labels separated by dots, like "sub" in sub.example.com, ending in a TLD (top-level domain) like .com or .org. The tool checks the length, characters, and structure of each label.

Valid domain names use letters, numbers, and hyphens, but cannot start or end with a hyphen, and have length limits per label and overall. The tool applies these rules to flag common errors.

Validating the format does not guarantee that the domain is available for registration. For that, you need to query the registry or a WHOIS service, which the tool does not do.

Examples

  • example.com or api.mydomain.com.br → valid.
  • -example.com or example..com → invalid (hyphen at the start or two consecutive dots).

Limitations

  • Validation checks the structure, not the availability for registration nor the existence of the domain.
  • Internationalized domains (IDN) use punycode (xn--) and may be handled specifically.

How to use the domain validator

  1. 1Type or paste the domain name into the main field.
  2. 2Click Process.
  3. 3See whether the structure is valid or invalid.

Frequently asked questions

Does validation say whether the domain is available?

No. It only checks whether the format is valid. Availability requires a registry or WHOIS query.

Can I use hyphens in the domain?

Yes, hyphens are allowed in the middle of the name, but not at the start or end of a label.

What is the difference between a domain and a URL?

The domain is just the name (example.com). The URL includes protocol and path (https://example.com/route).

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