Privacy policy
As of: 30 October 2026
This English version is a courtesy translation. The German version is legally binding.
Who is responsible
The operator of checkmaster.net is responsible for the processing of your data. Name and contact details are in the imprint.
Which law applies
We are based in Switzerland and process data under the Swiss Federal Act on Data Protection (FADP). For visitors from the EU and the United Kingdom the GDPR and the UK GDPR apply as well. We process data on the basis of our legitimate interest (Art. 6(1)(f) GDPR) in providing the free check, protecting it against abuse and improving it.
Which data we process
For the website check we store the website address entered and the result of the check, including screenshots of the home page. You do not need an account or an email address.
If you reach us through a campaign link or from another website, we store the name of the campaign and the domain of that website with the check. We also count how often a report is opened.
To protect against abuse we briefly use your IP address to limit the number of checks per hour.
How long we keep data
A report can be opened via its link for 30 days. After that the link no longer works and we delete the screenshots. We keep the website address and the check results to evaluate and improve the checks, for example how often a check fails over time. We do not publish them and do not pass them on. Backups of the database are kept for 14 days; Matomo keeps its raw data for 180 days.
Hosting and server logs
The website runs on servers of Infomaniak Network SA in Switzerland. For every request the web server logs the IP address, time, page requested and browser. The logs serve the secure operation of the site and are deleted after 14 days.
Cookies and audience measurement
We set no cookies for advertising or analytics and embed no content from third parties. When you submit the form, your browser briefly sets a technical cookie that protects against forged requests.
We measure the use of the website with Matomo on our own server in Switzerland. Matomo sets no cookies for us, reads no features of your browser and stores your IP address only in shortened form. The address of the website checked and the link to your report are not recorded. The data goes to no third parties.
If your browser sends the "Do Not Track" or "Global Privacy Control" signal, we do not measure your visits. You can also object to the measurement here. Your browser remembers this in the local storage of this website; nothing is sent to us.
Services we use for the check
For the check we send details about the website checked to the following services. We do not pass on your IP address.
- Google PageSpeed Insights (measurement of loading time; the address checked is sent to Google)
- W3C Markup Validator (check of the HTML code; the HTML code of the home page of the website checked is sent to the W3C)
- endoflife.date (comparison of software versions; only the name of the software is sent)
- ipwho.is (location of the server of the website checked; its IP address is sent)
- Google Chrome UX Report (loading times measured by Chrome users; the address checked is sent to Google)
- Google Public DNS (check of the DNS signature; the domain checked is sent to Google)
- wpvulnerability.net (known vulnerabilities of WordPress plugins; only the names of the plugins are sent)
- Anthropic (Claude) in the USA, only for extended checks that we start ourselves: the address and the text of the home page of the website checked are sent to identify the company and to ask AI assistants about it
Google and Anthropic process data in the USA. Both are certified under the EU-US Data Privacy Framework and its Swiss and UK extensions; data about you as a visitor does not go to them.
If your website was checked
The check only reads publicly visible information. If your website was checked without your knowledge, we will delete the report on request and exclude your website from further checks. More under Our crawler.
Your rights
You can ask for information about your data and for its correction or deletion, and object to its processing. We delete a report immediately on request. Please send us an email.
You can also lodge a complaint with a data protection authority: in Switzerland the Federal Data Protection and Information Commissioner (FDPIC), in the EU the authority of your country, in the United Kingdom the Information Commissioner (ICO).
Notice for residents of US states
We do not sell or share personal information and use it for no targeted advertising. We set no tracking cookies, so a Global Privacy Control signal needs no further action. You have the rights described above; to use them, send us an email.