CalculatorPeak is a free library of online calculators for maths, personal finance, health, construction and everyday life. Every calculator is free to use, needs no account, and runs in your browser.
What makes our calculators different
- Every result shows the formula and the working, step by step, so you can check it rather than trust it.
- Every calculator comes with a plain-English guide: how to use it, a worked example, what the result means and the mistakes people commonly make.
- The numbers in our examples and FAQs are checked against the calculator itself by automated tests, so the explanation and the answer always agree.
- Metric and imperial units are supported wherever they matter.
Where the formulas come from
We use the established, published methods for each calculation — for example the WHO growth standards for child percentiles, the CKD-EPI 2021 equation for kidney function, standard amortisation for loans, and manufacturers’ published coverage rates for building materials — and say in each guide which method is used and where its limits are.
A note on advice
Our calculators give estimates for information and education. They are not financial, medical, legal or engineering advice. Please read our disclaimer before relying on a result for an important decision.
Contact
Get in touch: hello@calculatorpeak.com