What this site keeps, and what it does not.
Block The Chain 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 21 September 2026.
Block The Chain
Registered with the Dutch Chamber of Commerce under KvK number 84616458. Established in the Netherlands. Contact for anything on this page: [email protected]. Reply within one business day.
What is stored when you send a scoping request
Your name, work e-mail, organisation, preferred slots, your message, the time of sending, your IP address, the country derived from it and your browser type. The IP address and browser type are kept to stop abuse of the form. Legal basis: taking steps at your request before entering into a contract, and the legitimate interest of keeping the form usable.
Twelve months, or sooner on request
Messages 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. Rate-limit counters that hold only an IP address expire after one hour. Ask and a message is deleted earlier.
Who touches the data
Cloudflare, Inc. hosts the site, stores form submissions and serves DNS; submissions live in Cloudflare's key-value store, which replicates across its global network under Cloudflare's data processing addendum. Microsoft 365 provides the mailbox that receives messages. Resend, Inc. forwards form submissions to that mailbox. No data is sold or shared with anyone else.
The free tools never send data to Block The Chain
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.
One preference, no tracking
The site stores your colour and light or dark preference in one first-party cookie and in your browser's local storage. That is all. No analytics, no advertising, no third-party cookies, no fingerprinting. Because the only cookie is a functional preference, no consent 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 to [email protected] from 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.