About toolsapp.work

toolsapp.work is a free collection of 42 calculators, unit converters, timers and developer utilities, organised as six lines on one map. Every tool runs in your browser, needs no account and shows the formula it uses, so you can check the answer yourself.

What is on the map

The tools are grouped into six lines. A tool that belongs to two subjects, such as the currency converter, sits where two lines cross.

• M Math: arithmetic, percentages, geometry and dates (5 tools).
• H Health: body composition, fitness and nutrition (6 tools).
• $ Money: loans, savings, budgets and exchange rates (7 tools).
• C Converters: every unit of measurement, both ways (10 tools).
• D Digital: encoding, security and colour utilities (7 tools).
• T Time & Text: timers, schedules and writing helpers (7 tools).

Alongside the tools there are 49 guides that explain the maths behind them with worked examples.

Why the tools are free

Everyday calculations should not sit behind a subscription, an app install or a sign-up form. Premium calculator apps can cost more than many people want to pay for a single answer, many free ones ask for an account or collect personal data, and heavy apps leave out people on older devices. A fast page that works in any modern browser solves all three.

How we keep the numbers right

Each tool implements a published method, such as the WHO adult BMI categories, the Mifflin-St Jeor energy equation or the exact SI definition of an inch, and the page shows that formula next to the result. Results are checked against worked examples from the original sources before a tool goes live. The methodology page lists every formula and standard we use.

The tools give estimates for planning and learning. They are not medical, legal or financial advice, so confirm important figures with a qualified professional.

Privacy in practice

• Calculations happen in your browser. The numbers and text you type into a tool are not sent to our servers or stored after you close the page.
• There are no accounts and no sign-up.
• We use Google Analytics to count page views and see which tools are useful. It sets cookies and receives standard browser data such as your IP address.
• The currency converter downloads daily exchange rates from a public rates service when you open it.
• Your light or black theme choice is saved in your browser's local storage.

The full details are in the privacy policy.

Teachers and students

You are welcome to link to any tool or guide from lesson plans, coursework and school websites. Each tool page has a stable address, and the formula section makes the tools useful for checking working, not only answers.

Get in touch

Found a wrong result, a typo or a tool you would like to see on the map? Email support@toolsapp.work or use the contact page.