MinuteMetric - Free Online Calculators for Health, Finance, Fitness & More

MinuteMetric is a collection of free calculators and estimation tools for the questions that come up in ordinary life — how much concrete a patio needs, how long a debt will take to clear, what pace to hold for a target race time, how much it costs to charge an electric car, what a recipe looks like scaled for nine people instead of four.

Every tool runs entirely in your browser. There's no sign-up, nothing to install, and the numbers you enter stay on your own device rather than being sent to a server. Each calculator works on a phone as readily as a desktop, because most of these questions come up when you're standing in a shop or a garden rather than sitting at a computer.

What You'll Find Here

Health & fitness — BMI, body fat, daily calories, macros, hydration, heart-rate zones, sleep timing and VO2 max.
Finance — loan and mortgage payments, compound interest, debt payoff strategies, savings goals, emergency funds and budget breakdowns.
Strength & endurance — one-rep max estimates, strength standards, Wilks scores, training pace, race time prediction and split times.
Home & DIY — paint, tiles, flooring, decking, wallpaper, concrete and room area.
Vehicles & travel — fuel costs, road trip planning, travel budgets, EV charging costs and electric versus petrol comparisons.
Environment — carbon footprint, home energy use, water consumption, recycling impact and solar savings.
Sport match quizzes — find out which sports your build actually suits, including Olympic and Commonwealth Games events.
Everyday tools — percentages, tips, bill splitting, date calculations, recipe scaling, unit conversions and random generators.

How We Build These Tools

Our calculators use established, published formulas — standard amortisation maths for loans, MET values for exercise energy cost, the Mifflin-St Jeor equation for metabolic rate, Naegele's rule for due dates. Each page sets out the formula it uses and works through an example, so you can check the result yourself or adapt the method to a situation we haven't covered.

We're also explicit about limitations. An estimate is labelled as an estimate, and where a tool simplifies something we say so on the page rather than letting a confident-looking number imply more precision than it has. These are general-purpose tools, not professional advice: for medical questions, significant financial decisions or structural work, use them to understand the shape of the problem and then talk to someone qualified.

You can read more about our approach on the About page, or tell us about an error or a calculator you'd like to see via Contact.