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Website Checker

Enter a URL to see if the site is online, how old its domain is and when it expires, who its registrar is, if its security certificate is valid, and its DNS and Whois records. Any URL can be checked, not just a tracked Dodolytics website. Free tool, nothing you check is stored.

One limit: most registries hide the owner of a domain, so the Owner tab is frequently empty.

How to use

1
Enter a domain or URL in the field above. A bare domain, a subdomain, or a full URL all work.
2
Click Check website.
3
Read the summary line and any warnings first. Then browse the six tabs: Overview, Registrar, Owner, DNS, Certificate, and Whois.

Tip: an empty Owner field usually means the registry itself is withholding it, not that this check failed.

What is a website checker tool?

A website checker looks up the public facts about a site and its domain: when the domain was registered and when it expires, who the registrar is, whether the site is reachable right now, whether its security certificate is valid, and what its DNS records say. It's pulled from the domain's real RDAP and Whois records, a live HTTP check, a live TLS connection, and live DNS queries, rather than anything the website itself claims about itself.

How do I use it?

Enter a domain or URL above. This tool checks the site's live availability, looks up the registration data of its registered domain (creation date, expiration date, registrar, name servers, DNSSEC status, registrant), reads its security certificate and its DNS records (addresses, mail servers, SPF, and DMARC), and fetches its raw legacy Whois record too. A summary line and any warnings are at the top, and the detail is in six tabs: Overview, Registrar, Owner, DNS, Certificate, and Whois.

Why is it useful?

Quickly check when a domain was registered and how much longer it has before it expires, useful before buying or evaluating a domain, or keeping an eye on one you already own.
Confirms a site is actually up and responding right now, rather than just assuming it is.
Warns you when a domain or a security certificate is near its end date, before the site stops for your visitors.
Surfaces registrar, name servers, mail servers, and DNSSEC status in one place, useful for due diligence or troubleshooting a domain issue.
Free, no sign-up required, and nothing about a check is stored. Check any domain, not just one you already track.

FAQ

Is this tool free?

Yes, no login required either.

Do you store the URLs I check?

No. Nothing about a check is saved anywhere. It's shown once, in the same response, and gone.

Why is the Owner tab often blank?

Most registries redact registrant (owner) data by default since 2018, under GDPR and ICANN policy. A blank owner means the registry itself withheld it, not that this check failed.

Where does this data come from?

A live RDAP lookup for the registration facts, a live legacy Whois query for the raw record, a real HTTP request to check availability, a real TLS connection for the certificate, and live DNS queries. When the registry gives no structured dates, the dates are read from the Whois record, and the page says so.

I entered a subdomain. Which domain is the data for?

For the registered domain. A registry knows example.com, not www.example.com or blog.example.com, so the tool finds the registered domain of the name that you entered and says which one it used. Availability, the certificate, and the addresses are for the exact name that you entered.

What is the difference between "Error" and "Down"?

"Down" means that no server answered. "Error" means that a server answered, but with an error status such as 404 or 500, or with a certificate problem. An answer that refuses this tool (403, for example) also shows as "Error", and such a site possibly works in a browser.

What does the Certificate tab check?

It reads the security certificate that the site shows on port 443 and tests it the way a browser does: is it in date, is it for this name, and is it from a trusted authority. You get a warning when it has less than 14 days left.

What are SPF and DMARC on the DNS tab?

Two DNS records that protect the email of a domain. SPF lists the servers that can send mail for the domain. DMARC says what a receiver does with mail that fails the checks. A domain that sends email and has neither can find its mail in spam folders.

Why does the Whois tab look unformatted?

It's the registry's own raw response, shown exactly as returned. Whois has no consistent format across registries, unlike the structured RDAP data in the other tabs. Use the Copy button to take the full text.

What if a domain isn't found in the registry?

It likely means the domain is expired or was never registered. The Overview tab will say so directly.

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