Privacy policy

Last updated 16 October 2026

The short version

Everything is worked out in your browser. The calculators never send your figures anywhere, whether it's your salary or a property price, and there is no account to create. If ads are shown in future, Google's ad scripts run on the page under Google's privacy policy, and Google may use cookies to choose ads, as explained below.

What stays on your device

Your settings. Your light or dark theme, the tools you pin, your world clock cities, and the calculator's mode (basic or scientific) and angle setting (degrees or radians) are saved in your browser's local storage. Clearing your browser data removes them.
Offline copy. Your browser keeps a copy of the site's own files so the tools work without an internet connection. It holds no figures you enter and nothing from ads.
Results links. When you choose “Copy link”, the calculator's inputs are added to the link so the result can be shared. Anyone you send that link to can see those figures. They go after the # in the link, a part browsers don't send to the web server. When a results link is opened, the figures fill in the calculator and are then removed from the page address.

What we don't collect

We use Cloudflare Web Analytics to count visits and see which calculators are used. It sets no cookies, doesn't track you across sites and doesn't collect your figures. Your browser's Do Not Track or Global Privacy Control setting turns it off. Cloudflare handles this data under its privacy policy. There are no other analytics or tracking scripts, and no forms that send your details anywhere. Fonts and icons are served from this site, not from a third party.

Advertising

To keep the tools free, the site may show ads provided by Google AdSense. When ads are shown:

Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website or other websites.
Google's use of advertising cookies enables it and its partners to serve ads to you based on your visit to this site and/or other sites on the internet.
You can opt out of personalised advertising in Google's Ads Settings. Read how Google uses information from sites that use its services.
Visitors in the European Economic Area, the UK and Switzerland are asked for consent before personalised ads are shown.

Ad scripts can see the address of the page you're viewing. Calculator inputs are kept out of the page address while you use a tool, and nothing you type is sent to us or to advertisers by the calculators themselves.

Other services

Hosting. The site is hosted on GitHub Pages. GitHub may log visitors' IP addresses for security, as described in the GitHub Privacy Statement.
Buy Me a Coffee. If you choose to support the site, the payment is handled on Buy Me a Coffee's website under its own privacy policy. We don't see your card details.
Affiliate links. Some pages have a "Tools I use" box with affiliate links to non-financial products such as books and software. If you buy or sign up through one, the seller tells us a purchase came from this site so we can be paid a commission; they handle your details under their own privacy policy. We don't receive your name or payment details, and the links don't change any calculator result.
Links to official sites. Links to the ATO, Revenue NSW and other sites take you to services with their own privacy policies.

Changes and contact

If this policy changes, the date at the top will change too. The terms of use cover how the calculators may be used and shared.