How to use Domain name inspector
Inspect ASCII domain labels, IDN conversion and hostname length without performing a DNS lookup. The check runs when you submit the form. Its inputs are processed in this browser.
How the check works
The browser’s URL parser converts an internationalised hostname into ASCII. The tool then checks label lengths and the ordinary hostname character rules.
The Overview tab explains the findings. Measured data lets you search individual fields and values, while JSON report shows the complete export. Export JSON to retain a baseline, or print the findings for your own records. Review the report before sharing it: browser characteristics, token claims, and file names can reveal information about your setup.
Read the result in context
An xn-- label indicates an internationalised name. Compare the actual ASCII form when checking a look-alike hostname. The last label is shown without claiming it is a public suffix.
Understand the limits
Registration, ownership, DNS existence and domain reputation are not checked. A public-suffix dataset is not included.
Common questions
Where is the input processed?
In this browser tab. This tool does not submit its input to the site server or a third-party service.
What should I keep with a result?
Record the selected options, browser and time. Review exported values before sharing them. Generated passwords, tokens and HMAC secret keys are excluded from report exports.