Privacy policy

Updated 5 November 2026. This notice describes the implemented website. The operator must review its identity, applicable requirements and provider settings before the final public launch.

Calculator inputs

Calculations run on your device. The public calculator does not send its numeric inputs to a server, store them in local storage, or require a visitor account.

Private contact messages

The contact form collects the name, reply email, subject and message you submit, plus your acknowledgment of this notice. It sends those fields over HTTPS to a private inbox available to the authenticated owner. Message bodies are encrypted by the application before storage in the site's dedicated Cloudflare D1 database; decryption requires a separate Worker secret. They are not committed to the website's GitHub source repository.

Messages remain available in the inbox for 30 days. Daily cleanup removes expired records within the following 24 hours, so live storage may retain them for up to 31 days. Provider backups and infrastructure retention follow the operator's Cloudflare settings and provider policies. Archiving changes the inbox view; it does not extend retention. Do not send passwords, access tokens, financial details or other sensitive information.

The form uses a short-lived timing token, an empty honeypot field and request rate limits to reduce abuse. Request IP information is used for rate limiting; the application does not store it alongside contact messages. A receipt confirms storage, not an email delivery, response time or promised reply. Use the contact form for a privacy or correction request and include the receipt reference where relevant.

Editor authentication

The private dashboard verifies the approved editor's email and password over HTTPS. It stores a salted password verifier and a separate signing key, not the original password. Signed sessions use a Secure, HttpOnly, SameSite cookie lasting up to eight hours. Login attempts are rate limited. Editorial source and commit history are stored in the owner's GitHub repository.

Public cookies, analytics and banners

The public calculator does not set application cookies and contains no analytics or third-party tracking scripts. If enabled, sponsored image or text banners are labeled and use sponsored links. Following a source or sponsored link opens an independently operated service with its own privacy practices.

Hosting requests

Cloudflare receives request information such as IP address, requested URL and browser headers when serving or securing the website. Logging, security processing, data location, backups and retention depend on provider behavior and account configuration. Read Cloudflare's privacy policy for provider information.

Changes

New analytics, advertising networks, message-delivery providers or data uses would require a corresponding policy review. This page does not claim that provider settings or legal compliance have been independently certified.