Launching soon — 5,700+ tools in final testing
Bookmark this page and leave your email below to hear the moment it opens. Every calculator will be free, none will ask you to create an account, and none will hide a result behind a paywall.
See what's launchingPick the category closest to your problem and the tool is usually two clicks away. Each calculator shows the formula it used and explains the result, so you can check the working rather than trust a number.
Work out what a loan actually costs, how long savings take to reach a target, and what inflation does to a salary over ten years. Amortisation schedules break down every payment into principal and interest.
Loan repayment · Compound interest · Mortgage · EMI · Inflation · Salary · Tax · Credit score impact
Body composition, daily energy needs and training targets, each with the formula named so you know whether you're getting Mifflin–St Jeor or Harris–Benedict. Results include the ranges, not just a single number.
BMI · BMR · TDEE · Body fat · Calorie intake · Macros · Heart rate zones · Water intake · Pregnancy due date
Circuit maths and running costs in one place. The electricity usage tool prices an appliance by wattage and hours, and includes a reference table of typical draws so you can check your own assumptions.
Electricity usage · Ohm's law · Voltage drop · Wire size · Resistor colour code · Battery life · Power factor · Solar panel sizing
Estimate materials before you order them. Volume, mix ratios and load figures for site work, reviewed against standard structural practice rather than pulled off a forum post.
Concrete volume · Concrete mix ratio · Square footage · Brick & block count · Tile · Paint coverage · Roof pitch · Load bearing · Rebar
The small sums that come up weekly. Splitting a bill, working out a discount, counting days to a deadline, converting a height someone quoted in feet when you think in centimetres.
Percentage · Tip & bill split · Discount · Age · Date difference · Time duration · Fuel cost · Random picker
Grade maths for students who need an answer before results day. Work backwards from a target grade to find the mark you need on the final paper, or convert between grading scales.
GPA · CGPA · Percentage to GPA · Final grade needed · Weighted average · Test score · Attendance · Study time
Arithmetic through to statistics, with the steps shown. Where a result depends on which convention you use — sample versus population standard deviation, for instance — the tool says which one it applied.
Scientific · Fraction · Standard deviation · Mean, median, mode · Probability · Quadratic · Matrix · Triangle · Circle · Prime check
Running costs and performance figures for cars and bikes. Compare fuel economy across units without converting by hand, or price a journey before you commit to the drive.
Fuel efficiency · MPG to km/l · Trip cost · EV charging cost · Horsepower · Torque · Tyre size · Gear ratio · 0–60 estimate
Lab and coursework calculations with units handled properly. Enter a formula and get molar mass without counting atoms, or dilute a stock solution to the concentration you actually need.
Molar mass · Molarity · Dilution · pH · Ideal gas law · Percent yield · Empirical formula · Half-life
Mechanics, waves and thermodynamics for homework and quick sanity checks. Each tool states its assumptions, so you know when air resistance has been ignored and when it hasn't.
Velocity · Acceleration · Force · Kinetic energy · Projectile motion · Momentum · Density · Wavelength · Pressure
Recipe maths that respects the difference between weight and volume. Grams to cups depends on the ingredient, so these conversions ask which one you're measuring instead of guessing.
Grams to cups · Recipe scaling · Oven temperature · Cooking time · Baking substitutions · Serving size · Nutrition per portion
Environmental impact in numbers you can act on, plus the biology calculations that turn up in coursework. Carbon figures are traceable to a stated emissions factor rather than a vague average.
Carbon footprint · Water usage · Recycling impact · Tree offset · Population growth · Punnett square · Cell dilution · Enzyme activity
Academic specialists check the maths behind each category.
Every result names the formula and the assumptions it made.
Calculations run in your browser. Your inputs never leave it.
Full functionality on a phone, no app to install.