All calculators

Acceleration from change in velocity over time.

Add or subtract days from a date.

Your exact age in years, months, days and total days lived.

Solve linear equations of the form ax + b = c.

Convert degrees, radians, gradians and turns.

Effective annual yield from a nominal rate.

Convert area between 6 units instantly with full precision.

nth term and sum of an arithmetic progression.

Convert text to ASCII character codes.

Attendance percentage and classes needed to reach your target.

Mean, sum and count for a list of numbers.

Particles in a given number of moles.

Encode text to Base64 or decode it back.

Add, subtract, multiply and divide two numbers.

Required V-belt length between two pulleys.

Convert decimal numbers to binary and back.

Probability of exactly k successes in n trials.

Days left until your next birthday.

Estimated BAC using the Widmark formula.

Body Mass Index from height and weight, with WHO category.

Basal metabolic rate using the Mifflin-St Jeor equation.

Estimate body fat percentage with the US Navy method.

Mosteller BSA, widely used for dosing.

How solutes raise a solvent's boiling point.

Units you must sell to cover fixed costs.

Compound annual growth rate between two values.

Daily calorie needs based on activity level and goal.

Total capacitance in series or parallel.

Monthly payment and total cost for a vehicle loan.

Force keeping an object in circular motion.

Cumulative GPA across semesters, with percentage conversion.

Check mass balance between reactants and products.

Mid-parental height estimate for a child.

Area, circumference and diameter from a radius.

Your percentile rank within a class.

Coffee grounds and water for a perfect brew.

Commission earned on a sale at any rate.

See how money compounds over time with any compounding frequency.

Concrete needed for a slab, with a waste allowance.

Convert cups, tablespoons, millilitres and grams.

Time remaining until an important date.

See how long it takes to clear a card balance.

Profit, loss and ROI on a crypto trade including fees.

Convert between currencies using your own exchange rate.

Convert data storage between 7 units instantly with full precision.

Days, weeks and months between any two dates.

Countdown in days from today to any date.

Check the DTI ratio lenders use to approve loans.

Convert a number between any two bases (2–36).

Density from mass and volume.

Convert between common density units.

Final price after a percentage discount and how much you save.

How much cash you need upfront for a purchase.

Monthly electricity cost from appliance usage.

How much cash cushion you should keep.

Work out the exact monthly instalment for any loan, plus total interest.

Mass-energy equivalence and total mechanical energy.

Convert energy between 7 units instantly with full precision.

Solve simultaneous linear equations in two variables.

Speed needed to escape a body's gravity.

Raise any base to any power.

Compute n! for any reasonable value of n.

Maturity value of a fixed deposit with quarterly compounding.

How long a download or upload will take.

The score you need on the final to hit your target.

Estimated CO₂ emissions from a flight.

Convert L/s, m³/h, GPM and CFM.

Newton's second law: force from mass and acceleration.

Convert newtons, pound-force and kilogram-force.

Add, subtract, multiply or divide two fractions.

Fall time and impact speed from a height.

Convert hertz, kilohertz, megahertz and RPM.

Total fuel cost for any journey.

Convert between km/l, MPG and litres per 100 km.

Ideal gas law solved for pressure.

Greatest common divisor using the Euclidean algorithm.

Gear ratio and output speed from tooth counts.

nth term and sum of a geometric progression.

Area and perimeter of common 2D shapes.

Split a gift budget across a list of people.

Grade point average from credit hours and grade points.

Final grade from weighted assessment scores.

Add or remove GST at any rate with a full tax breakdown.

Remaining quantity after radioactive decay.

Fast non-cryptographic checksum for any string.

Healthy weight range for your height based on BMI 18.5–24.9.

Maximum heart rate and training zones by age.

Buffer pH from pKa and the base/acid ratio.

Convert hexadecimal values to decimal and binary.

Convert a hex colour into RGB and HSL.

Convert an hourly wage into weekly, monthly and yearly pay.

Daily worked hours minus break time, plus pay.

Devine formula ideal body weight from height.

What today's money will be worth in the future.

Simple interest on any principal, rate and duration.

How long a download takes at a given connection speed.

Project the future value of a lump sum plus regular contributions.

Validate and pretty-print JSON instantly.

Energy of a body in motion.

Lowest common multiple of two numbers.

Estimate fat-free mass using the Boer formula.

Check whether any year is a leap year.

Estimate a monthly vehicle lease payment.

Convert length between 9 units instantly with full precision.

Estimate repayments, total cost and interest for personal or auto loans.

Work out the monthly instalment on any loan.

Log of a number in any base.

Placeholder text for mockups and layouts.

Turn a calorie target into protein, carb and fat grams.

Total marks, percentage and grade from obtained scores.

Selling price from cost and desired markup.

Determinant and inverse of a 2×2 matrix.

Middle value and most frequent value in a data set.

What a meeting costs in salaried time.

Moles of solute per kilogram of solvent.

Molar mass from mass and number of moles.

Concentration from moles and solution volume.

Moles from mass and molar mass, plus particle count.

Linear momentum of a moving body.

Estimate home loan repayments including taxes and insurance.

Assets minus liabilities in one number.

Net present value of an even annual cash flow.

Solve for voltage, current or resistance.

Thin lens equation: image distance and magnification.

Total pay including overtime multiplier.

Fertile window and ovulation day from your cycle.

Running pace per kilometre and mile from distance and time.

Litres of paint needed for a room.

Entropy and estimated crack time for a password.

Swing period of a simple pendulum.

Increase or decrease between two numbers.

Reaction efficiency from actual vs theoretical yield.

Find what percent one number is of another, instantly.

Convert marks percentage into CGPA on a 10-point scale.

nPr and nCr for counting problems.

Daily food portion and how long a bag lasts.

pH and pOH from hydrogen ion concentration.

Volumetric flow from pipe size and velocity.

Which pizza size is actually better value.

Evaluate a cubic polynomial at any value of x.

Break a study session into focus and break blocks.

Gravitational potential energy at a height.

Power from work done over time.

Convert watts, kilowatts, horsepower and BTU/h.

Real, apparent power and the resulting power factor.

Estimated due date from the first day of your last period.

Hydrostatic pressure below a fluid surface.

Convert pressure between 6 units instantly with full precision.

Check if a number is prime and see its factors.

Single and combined event probability.

Profit, margin and markup from cost and selling price.

Range, max height and flight time of a projectile.

Solve a/b = c/x for the missing value.

Daily protein target based on weight and goal.

Find the hypotenuse or a missing leg.

Roots of ax² + bx + c = 0 with discriminant analysis.

Generate random numbers in a range.

Simplify a ratio and scale it to a new total.

How long a piece of text takes to read.

Test a regular expression against sample text.

Decode 4-band resistor colour codes into resistance.

Project your retirement corpus and how long it will last.

Return on investment as a percentage and multiple.

Square, cube and nth roots.

Surface speed from rotational speed and diameter.

How many years until your money doubles.

Break an annual salary into monthly, weekly and hourly pay.

Add or remove sales tax from any amount.

How much your savings grow with regular monthly deposits.

Free online scientific calculator: trig, log, exponential, power and root functions.

How much of your life goes to screens.

Flat interest on a principal amount.

Future value of a monthly systematic investment plan.

Best wake-up times based on 90-minute cycles.

What a smoking habit costs over time.

Dilution using C1V1 = C2V2.

Convert speed between 5 units instantly with full precision.

Volume and surface area of a sphere.

Divide a bill evenly, including tax and tip.

Hooke's law stiffness from force and extension.

Mean, median, mode and standard deviation of a data set.

Weight of a round steel bar.

Daily study hours needed to cover your syllabus in time.

Mask, host count and wildcard from a CIDR prefix.

Estimate tax payable on income using a flat or slab rate.

Total daily energy expenditure from BMR and activity.

Convert between Celsius, Fahrenheit and Kelvin.

Convert text between common naming cases.

Line current from three-phase power and voltage.

Tiles needed for a floor or wall, with wastage.

Convert between seconds, minutes, hours, days and years.

Hours and minutes between two times.

Convert a local time across UTC offsets.

Tip amount and total bill, split across your group.

Torque from force applied at a distance.

Convert Nm, lb-ft and kgf-m torque values.

Turns ratio and secondary voltage.

Total trip budget across travel, stay and food.

Heron's formula area from three sides.

Words per minute adjusted for accuracy.

Compare grocery deals by price per unit.

Convert a Unix timestamp into a readable date.

Percent-encode or decode a URL string.

Turn any title into a clean URL slug.

Generate an RFC-4122 version 4 UUID.

Velocity from displacement and time.

Aerobic fitness estimate from a 12-minute run.

Output voltage across a two-resistor divider.

Convert volume between 7 units instantly with full precision.

A quick cardiovascular risk indicator.

Calories burned on a walk.

Rolls of wallpaper needed for a room.

Recommended daily water intake for your body weight.

Electrical power from voltage and current.

Frequency from wave speed and wavelength.

ISO week number for any date.

Convert weight between 7 units instantly with full precision.

Combine assignment scores with their weights.

Words, characters and sentences in any text.

Mechanical work from force, distance and angle.

Business days between two dates, excluding weekends.