Domain Name Validator
Check domain names against the label and length rules of DNS.
Your result will appear here as soon as you add some input.
How to use it
- 1Paste your input into the input box, or type it directly.
- 2Adjust the options if you need something other than the defaults.
- 3The result updates as you type.
- 4Copy the result to your clipboard or download it as a file.
About the Domain Name Validator
Labels must be 1-63 characters of letters, digits and hyphens, must not start or end with a hyphen, and the whole name must stay under 253 characters.
Internationalised domains have to be given in their punycode form - `xn--` - because that is what actually travels over DNS.
Questions people ask
Is your code uploaded to a server?
No. This tool runs entirely in your browser using standard web APIs, so your code never leaves your device. You can confirm it by opening your browser's network panel while the tool runs, or by disconnecting from the internet after the page has loaded.
Is it free, and do I need an account?
Yes, it is free, and there is no account, no sign-up and no watermark on the result. The project is funded by optional donations.