About Everything Calculator

Everything Calculator is a free collection of 40 calculators covering money, health, mathematics, dates and everyday household questions. The idea behind it is simple: one place, every calculation, with no sign-up and no clutter between you and the answer.

How our calculators are built

Each tool is written against a published, widely accepted formula rather than an approximation. Body-composition tools use the Mifflin-St Jeor and US Navy equations, loan tools use the standard amortisation formula, and statistics tools distinguish properly between sample and population measures. Every page shows the formula it uses and the intermediate steps of your specific calculation, so you can check the result by hand or reproduce it in a spreadsheet.

What we do not do

We do not give medical, legal or financial advice. A calculator applies a general formula to the numbers you type; it knows nothing about your medical history, your tax position or your lender's specific terms. Where a result should be treated as an estimate, the page says so plainly, and where a decision is significant we say the same thing every time: speak to a qualified professional.

Corrections

If you find a calculation you believe is wrong, we want to know. Send the calculator name, the exact inputs you used and the result you expected via the contact page and we will check it.

Privacy and speed

Calculations run entirely in your browser. The numbers you enter are never transmitted to a server or stored by us. The site is built to load quickly on a phone with a poor connection, because a calculator that takes five seconds to appear is not much use.

Start with the calculator directory or browse by category.