Your data.
Plain and simple.

The calculator stays with you

The numbers and costs you choose are saved in this browser’s storage, so your plan is still there when you come back. The website doesn’t read the app’s flock database and never sends your assumptions anywhere. If you copy a link to your plan, it contains the chosen numbers — anyone you share it with will see them.

Your answer to the egg question on the home page also stays only in this browser and is never sent. The “Clear saved plan” button deletes the calculator settings. If browser storage is blocked, the calculations still work in the open tab.

Connections and external websites

The calculator, the story, the questions and this page load only 4Kurki’s own files. We don’t load external fonts. We count page views with Vercel Web Analytics — its file is served from our own domain, it sets no cookies, and plain page counting stores nothing in your browser. What gets recorded is the page address, the page you came from, an approximate location, your operating system, browser and device type — without your IP address and without tying any of it to a particular person. Visitors are recognised by a hash that is valid for one day only, so you cannot be followed between days or between websites. On the home page the YouTube player loads only after you click the video — that’s when your browser connects to YouTube (Google). The Facebook video opens in a new tab. Links to source material open their publishers’ websites.

Opening the app or a game takes you to a separate 4Kurki module (currently in Polish). The app can use an external weather forecast if you turn that feature on. The hosting provider may process ordinary technical connection data, including your IP address, as part of running the server.

The “Buy me a coffee” button is an ordinary link to buycoffee.to. Nothing loads until you click it, and once you do, their website opens under their own rules. All I receive is the fact that someone bought a coffee, along with whatever they chose to write. I do not know who clicked, and I do not connect it to your visit here.

The contact form

If you write through the contact form, what you put there — your name, email address and the message itself — is sent by email straight to my mailbox. It is not stored in any database on this website, and it does not go into a newsletter or a ticketing tool. The delivery itself goes through Resend, which passes the message on, much as any mail server does.

Your email address is used only to reply. The message then stays in my mailbox like ordinary correspondence. If you want it deleted, say so and I will delete it.

Diary backups are a separate thing

Browser storage is not an automatic backup on another device. You can download a backup of your flock records in the app settings. Deleting the plan on this page doesn’t delete the diary.

This describes the website as of 13 September 2026. It covers the public pages and the calculator; it is not a promise to sync flock data. If the English and Polish versions differ, the Polish version applies.