Cookie notice
*Working translation. The German version prevails.*
The platform does not use advertising, analytics or tracking cookies. Only the following storage is used:
Cookies
- Supabase sign-in cookie: keeps you signed in. Technically necessary.
- "__stripe_mid" (1 year) and "__stripe_sid" (30 minutes): set by the payment service provider Stripe on our domain when the payment form is loaded, used for fraud prevention in card payments (risk assessment of the payment attempt by Stripe under its own responsibility). Within the payment form, Stripe also sets cookies under its own domains (e.g. stripecdn.com, m.stripe.com) that are limited to the form. The payment form is only loaded if you have given your consent in the purchase dialog beforehand; without consent no Stripe cookies are set.
Browser storage (localStorage)
- "theme": selected display (light or dark)
- "auth_last_method": last sign-in method used
Projects of the calculation tools are not stored in browser storage; they exist only while the window is open and can be saved manually as a JSON file.
Consent and withdrawal
No consent is required for the sign-in cookies and the browser storage; they are strictly necessary for the service you have requested (§ 25(2) No. 2 TDDDG).
The Stripe cookies are only set with your consent (§ 25(1) TDDDG). You are asked in the purchase dialog before the payment form is loaded and you can decline; Stripe is then not loaded and card payment is not possible. Your decision is stored in the browser ("apex_payment_consent": text version, decision, time – without an identifier). You can withdraw your consent at any time at the bottom of this page or in the purchase dialog. On withdrawal, the Stripe integration is ended, the Stripe cookies on our domain ("__stripe_mid", "__stripe_sid") are deleted and the page is reloaded. Cookies that Stripe has set within the payment form under its own domains cannot be deleted by us; you can remove them in your browser settings. Withdrawal applies to the future.
Further information is available in the privacy policy.
Stand: 31.10.2026