What this site keeps, and what it does not.
BlockTheChain collects as little as the work allows. This page states exactly what is processed when you use blockthechain.nl, why, for how long, who handles it and how you exercise your rights. Last updated 24 September 2026.
BlockTheChain
Registered with the Dutch Chamber of Commerce under KvK number 84616458. Established in the Netherlands. Contact for anything on this page: the contact form. Reply within one business day.
One contact form; nothing stored on this site
The contact form sends your message straight to the BlockTheChain mailbox as an e-mail; this site keeps no copy. What arrives is what you typed: your name, your e-mail address, your organisation if you give it, and your message. Legal basis: taking steps at your request before entering into a contract.
Twelve months, or sooner on request
E-mails are kept for twelve months after the last contact, then deleted. If a message leads to an engagement, the relevant parts move into the engagement file, which follows the retention agreed in that engagement. Ask and a message is deleted earlier.
Who touches the data
Cloudflare, Inc. hosts the site, serves DNS, counts visits without cookies and passes the contact form on without storing it. Microsoft 365 delivers the message and provides the mailbox that receives it. No data is sold or shared with anyone else.
The free tools never send data to BlockTheChain
Every check runs in your browser and talks directly to the public source it names: MDN HTTP Observatory, Cloudflare DNS over HTTPS, Have I Been Pwned (five hash characters only), Ethereum public RPC nodes, Sourcify and 4byte. What you type goes from your browser to that source, not to this site. Their own privacy terms apply to those requests.
No cookies, no tracking
This site sets no cookies at all. Your accent colour, light or dark mode, the Simple or Pro view and your language choice are kept in your own browser's local storage, and never leave your device or reach a server. Visits are counted with Cloudflare Web Analytics: no cookies, no fingerprinting, no profile of you, only totals such as page views, the referring site and the country. Automated browsers are not counted. To leave your own visits out, open any page with #nocount at the end of the address (kept in your browser; #count undoes it). No advertising and no other third-party scripts. Because nothing is stored on your device that needs consent, no banner is required and none is shown.
Edge logs for security only
Cloudflare records requests to the site, including IP address and user agent, to detect and block attacks. These logs are held by Cloudflare for a short, fixed period and are not used to profile visitors. Requests without a browser signature may be rate-limited or blocked.
Access, correction, deletion, objection
You can ask what is held about you, have it corrected or deleted, restrict or object to its processing, or receive it in a portable form. Send the request through the contact form with the address you used; answered within one month. You can also complain to the Dutch Data Protection Authority, the Autoriteit Persoonsgegevens.
Security of the data in transit and at rest: HTTPS with HSTS, minimal collection, no copies outside the systems named above. Changes to this statement are dated at the top; material changes are also announced on this page.
One message starts it.
Thirty minutes to scope it. A fixed-price proposal within two business days.