Calculators

Choose a calculator from our collection

A free online basic calculator for addition, subtraction, multiplication and division, with memory keys and full keyboard support.

Free scientific calculator with trigonometry, logarithms, powers, roots and constants. Handles full expressions and parentheses.

Convert length, weight, volume, temperature, speed and more. Precise free unit converter with instant results in both directions.

Calculate voltage, current, resistance and power with Ohm's Law. Enter any two values and get the rest instantly for electronics work.

Work out selling price, cost, profit and markup or margin percentage. A free pricing calculator for retail and small business.

Work out a percentage of a number, express one value as a percentage of another, or find the percentage increase or decrease. Shows the working.

Estimate concrete volume in cubic yards or metres, plus bags or truckloads needed, for slabs, footings, columns and stairs.

Calculate how much flooring you need in square feet or metres, including the waste allowance for cuts, planks and diagonal layouts.

Work out board feet, linear feet and the number of studs or joists a framing project needs, with standard spacing options.

Estimate how many gallons or litres of paint a room needs from wall area, coats and door and window deductions.

Calculate roof area, squares of shingles, underlayment and bundles from your roof's dimensions, pitch and overhang.

Calculate square footage for any room or irregular floor plan, including odd shapes, L-shapes and multiple rooms at once.

Estimate monthly mortgage payments with principal and interest, plus taxes and insurance, and see total interest over the term.

Calculate monthly payments, total interest and the full amortisation schedule for car, personal and student loans.

Project investment growth with compound interest, regular contributions and different compounding frequencies over time.

Estimate how much you need to retire and whether your savings will last, based on age, contributions and expected returns.

Compare a high deductible health plan against a lower deductible one using premiums, deductible and expected out-of-pocket spend.

Estimate the calories you burn daily and how many to eat to lose, maintain or gain weight, using the Mifflin-St Jeor equation.

Calculate daily protein, carbohydrate and fat targets from your calorie needs and goal, with common diet split presets.

Calculate your Body Mass Index and weight category using WHO classifications, for adults and children in metric or imperial units.

Estimate body fat percentage using the US Navy tape method, BMI method or skinfold measurements, and track changes over time.

Find your target heart rate zones for fat burning, cardio and peak training, based on age and resting heart rate.

Convert Minecraft blocks into stacks and shulker boxes, and work out exactly how much material a build needs.