Pricing
Every calculator is free and will stay free for everyone. Donating is 100% optional: no paywall, no locked features.
Free access
- Full access to all 9 calculator categories, with no usage limits.
- Plain-language explanations of each metric and why it matters.
- We never block a calculation because you didn't donate or share your data.
When you support with a donation
- Ad-free browsing across the whole app.
- You help keep the project running and fund new calculators.
- You get a thank-you message (if you shared your email).
Choose your contribution
You pick the amount. Each unit equals $1 USD and you can adjust it before paying.
About payments
Payments are processed by Paddle.com Market Ltd, acting as Merchant of Record for the transaction. By donating you accept the following: