Health & Fitness
Body metrics, energy needs and everyday wellbeing numbers explained in plain language.
Free health & fitness calculators from CalculatorWonder. Every tool below runs instantly in your browser, states the formula and assumptions behind the answer, and never stores what you type.
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BMI Calculator
Body mass index from height and weight, with the category it falls into.
Body mass index is a quick screening figure comparing weight to height. It does not account for muscle mass, build or age, so treat it as one signal among many rather than a diagnosis.
Body mass index (BMI) is a quick screening figure that compares your weight to your height. It is widely used because it needs only two measurements and no equipment beyond a scale and a tape measure, and it gives a single number that falls into a standard category: underweight, normal weight, overweight, or obese. The BMI Calculator works out the index from your height and weight and shows which band it lands in.
Age Calculator
Exact age in years, months and days, plus a countdown to the next birthday.
Pick a date of birth and, if you like, a date to measure to. You get the precise age in years, months and days, the total days lived and how long until the next birthday.
The Age Calculator gives an exact age in years, months and days from a date of birth, rather than the rough whole-years figure most of us carry around. Pick your date of birth and, optionally, a date to measure up to — useful for forms, eligibility checks, or working out how old someone was on a particular day. The tool also shows the total number of days lived and a countdown to the next birthday.
Other categories
- Money & Finance — Mortgages, loans, interest, salary and long-term planning maths, worked out in seconds.
- Math & Science — Percentages, fractions, algebra, geometry and physics helpers for homework and work.
- Time & Date — Ages, gaps between dates, countdowns and time zone questions, answered exactly.
- Conversion — Switch between units of length, weight, temperature, volume and currency.
- Business & Productivity — Pricing, margin, break-even and return calculations for people running things.
- Household & Lifestyle — Rent, running costs, utilities and kitchen maths for the place you live in.
- Vehicle & Travel — Fuel economy, car finance and trip budgets before you turn the key.
- Education & Learning — Grades, averages and study finance tools for students and teachers.
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