Privacy Policy

Last updated: 1 November 2026

This policy explains what information DomainDNSCheck processes, why, and for how long. We have tried to describe our actual practices precisely rather than in general terms.

Who we are

DomainDNSCheck.com is an independent, free domain and DNS intelligence resource. If you have a question about this policy or want to make a privacy request, please use the contact page.

Anonymous tool use, accounts and cookies

Every tool, report and guide works without an account. An optional free account is needed only for domain monitoring.

• Public pages and tool results set no cookies of our own. Google Analytics may set analytics cookies on them, as described under Analytics; in the EEA, the UK and Switzerland only after you allow it.
• The contact form, sign-in and account pages use a session cookie and a CSRF (cross-site request forgery) token cookie. Both are strictly necessary for these features to work securely and are not used for tracking.
• The administration area uses session cookies for staff only. Staff accounts are separate from customer accounts.

Customer accounts

If you create an account, we store your name, email address, a one-way hash of your password (never the password itself), your language, your alert preferences and the time of your last sign-in. We use your email address to verify the account, to reset your password and to send the monitoring alerts you ask for. We do not send marketing email.

You can change your details or delete your account at any time from the profile page. Deleting the account immediately deletes your monitored domains, their check history and alert records.

Monitored domains and alert history

When you add a domain to monitoring, we store the domain name and your settings for it, and our servers check it on a schedule using the same public sources as the tools. For each monitored domain we keep:

Your list of monitored domains is private to your account. It is never published, shared with other users or given a public URL, and pages inside your account are excluded from search engines. Our staff can see monitored domains only for operating the service, for example to stop a check that keeps failing; they do not see your password.

Lookups

When you use a tool, the domain name, URL or IP address you enter is used to perform the checks you requested.

Caching

To reduce load on upstream services and respond faster, results are cached on our servers for a limited time. The duration depends on the type of check, roughly:

Cached results are stored under a hashed key and are not linked to you. We do not keep a permanent history of what visitors look up, and tool result pages are not published or indexed by search engines.

Third-party infrastructure

Performing a check requires sending the name you queried to external systems:

• Public DNS resolvers operated by Cloudflare and Google, for DNS lookups.
• RDAP servers run by domain registries, registrars and regional internet registries, for registration data.
• IANA, for the bootstrap data used to find the correct RDAP server.
• A public Certificate Transparency search service (currently crt.sh, operated by Sectigo), for the Certificate Transparency and passive subdomain tools. Only the registrable domain you enter is sent.

For SSL/TLS, HTTP and MTA-STS checks, our servers connect directly to the website or mail host you specify. Those connections come from our servers; your IP address is not passed to the hosts being checked. Each of these third parties handles the requests it receives under its own policies.

Abuse prevention and security

To protect the service and the systems it connects to, we apply rate limits and record certain security events.

• Rate limiting uses a keyed, one-way hash of your IP address. This hash is held in cache for up to 24 hours.
• Security events, such as blocked requests to private networks, rate-limit hits and failed administrator logins, are stored with a keyed hash that changes daily. These records are deleted after 30 days.

We do not store raw IP addresses in our application database.

Usage statistics

We keep aggregated hourly counters for each tool: the number of runs, successes and failures, and response times. These counters contain no domain names, IP addresses or other identifiers. They are kept for up to about 400 days so we can understand how the tools perform over time.

Analytics

We use Google Analytics 4, provided by Google, to understand which pages and tools are visited and how people find the site, so we can improve it.

• What is sent: the page address without its query string (so the domains, URLs and IP addresses you enter into the tools are never sent), the page title, the previous page on this site (also without query string) or the site you came from, and standard browser and device information. Google derives an approximate location from your IP address; Google Analytics 4 does not log or store IP addresses.
• Where: only on public pages. Account pages and the administration area never load Google Analytics.
• Cookies: _ga and _ga_<id>, which hold a random identifier for up to two years.
• Your choice: in the EEA, the United Kingdom and Switzerland, analytics cookies are set only after you select Allow in the banner. Elsewhere they are on unless you decline. You can change your choice at any time with Cookie settings at the bottom of every page; declining removes the analytics cookies. When analytics cookies are not allowed, the page may still send Google a signal without cookies or identifiers, which Google uses only for aggregated statistics.
• No advertising: advertising storage and ad personalisation are always switched off, and the data is not used for advertising by us.
• Retention: Google keeps the event data for the retention period set in our Google Analytics account (the default is two months); reports contain only aggregated figures.

Google processes this data under its own privacy policy. You can also block Google Analytics on all sites with Google's opt-out browser add-on.

Logs

Application error logs are kept for 14 days. They are designed not to include the domains, URLs or IP addresses you enter into the tools.

Our hosting provider may keep standard web server access logs, which can include IP addresses and requested URLs. Those logs are kept under the hosting provider's own retention policies.

Email delivery

Verification, password-reset and alert emails are sent through our email provider, which processes your email address and the message content to deliver them.

Contact form

If you send us a message, we store your name, email address, subject and message for up to 180 days so we can handle your enquiry, together with a keyed hash that changes daily to help us detect abuse of the form. Your message may be forwarded by email to our team for that purpose.

Advertising

DomainDNSCheck does not currently show advertising. The site may in future show ads from Google AdSense to cover running costs. Before any ads appear, this policy will be updated to explain the advertising cookies and identifiers involved, how Google and its partners use them, and how you can control personalised advertising (including consent choices where the law requires them).

What we do not do

• We do not show advertising at present.
• We do not send the domains, URLs or IP addresses you look up to any analytics service.
• We do not use tracking pixels or advertising cookies.
• We do not sell data.

Why we process information

We process information only where it is needed to:

• provide the tools and results you request;
• keep the service secure, reliable and protected from abuse;
• understand overall tool usage and performance through aggregated statistics and, where allowed, Google Analytics; and
• respond to messages you send us.

Where a purpose relies on our legitimate interests, such as security and abuse prevention, we limit the data involved and keep it for the shortest practical period.

Your rights

Depending on where you live, you may have rights over your personal information. In general, you can ask us to:

• access the account and contact-form information we hold about you;
• correct it if it is inaccurate;
• delete it before the normal retention period ends; and
• object to processing of your information.

Account holders can view, change and delete their own data directly in their account. Because anonymous lookups are not linked to individuals and security records use hashed identifiers that change or expire, we generally cannot identify records relating to a specific person outside of the contact form. To make a request, please use the contact page. We may need to confirm your identity, for example by replying to the email address you used, before acting on a request.

Changes to this policy

If we change how we handle information, we will update this page and the "Last updated" date at the top. We encourage you to review this page from time to time.

Contact

For privacy questions or requests, please reach us through the contact page.