Privacy Policy
Last updated: 5 November 2026.
The short version
The calculators run entirely in your browser. The numbers you type are never sent to a server, never stored, and never seen by anyone but you. There is no account, no login, and no profile.
What is collected
| Type | What it is | Why |
|---|---|---|
| Aggregate analytics | Page views, approximate country, device type, referrer | To know which pages are useful and which are broken |
| Advertising cookies | Set by third-party ad networks | To serve and measure ads that keep the site free |
| Calculator inputs | Nothing leaves your browser | Not collected, not transmitted, not stored |
Advertising
This site is supported by display advertising. Third-party vendors, including Google, use cookies to serve ads based on a visitor's prior visits to this and other websites. Google's use of advertising cookies enables it and its partners to serve ads based on visits to this site and other sites on the internet.
You can opt out of personalised advertising by visiting Google's Ads Settings, or opt out of third-party vendor cookies more broadly at aboutads.info. Visitors in the European Economic Area, the United Kingdom, and Switzerland are shown a consent notice before any non-essential cookie is set.
Children
This site is aimed at high school students and their parents. It does not knowingly collect personal information from anyone, of any age. Because nothing you type is transmitted, there is no store of personal data to delete.
Your rights
Because the site holds no personal data, there is generally nothing to access, correct, or erase. If you believe a third-party ad or analytics provider has stored data about you, contact that provider directly — they are the data controller for anything they set.
Changes
If this policy changes, the date at the top changes with it. Material changes will be noted on the home page for at least thirty days.
Contact
Questions about this policy: [email protected].