Domain Name Validator
Validate domain names against DNS naming rules. Shows labels, TLD, and whether it's a subdomain.
Domain names follow strict rules defined in RFC 1035 and RFC 1123. Each label (part between dots) must be 1–63 characters, consisting only of letters, digits, and hyphens — with no leading or trailing hyphens. The total domain length (including dots) must not exceed 253 characters. The TLD (top-level domain) is the rightmost label and must contain only letters. IDN (Internationalized Domain Names) use Punycode (xn-- prefix) to encode non-ASCII characters in DNS-compatible ASCII form.
Frequently Asked Questions
- Each label (segment between dots) must be 1-63 characters, contain only letters, digits, and hyphens, and not start or end with a hyphen. Total length must be ≤253 characters.
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