Science calculators
Kinematics, projectile motion, Ohm's law, resistor colour codes, circuits, optics, gas laws, molar mass, pH and radioactive decay, using CODATA 2022 constants and IUPAC atomic weights.
26 calculators · 183 checked examples
Mechanics
- Kinematics (SUVAT) calculator
Kinematics calculator for the SUVAT equations: enter three of displacement, initial and final velocity, acceleration and time to get the other two.
- Projectile motion calculator
Projectile motion calculator: range, maximum height, time of flight and impact speed for any launch angle and height, on Earth or other worlds, with drag.
- Centripetal force, moment of inertia and torque calculator
Centripetal force and acceleration from mass, speed and radius; rpm to rad/s and period; moment of inertia of nine shapes; torque from force and lever arm.
- F = ma calculator: force, friction and inclined plane
Solve Newton's second law F = ma for force, mass or acceleration, or find acceleration, normal force and friction for a block on an inclined plane.
- Horsepower calculator: torque, rpm and quarter-mile
Horsepower from torque and rpm (hp = lb-ft × rpm ÷ 5252) or from quarter-mile ET and trap speed, with crank vs wheel horsepower and drivetrain loss.
- Kinetic and potential energy, work and power calculator
Kinetic energy (½mv²), potential energy (mgh), spring energy, work (Fd cos θ) and power (W/t), solved for any variable, plus the speed after a drop.
- Momentum and collision calculator (elastic and inelastic)
Momentum and collision calculator: final velocities, total momentum and kinetic energy lost in an elastic, inelastic or partly elastic head-on collision.
- Orbital velocity and gravity calculator
Orbital velocity and period, escape velocity, surface gravity, your weight on the Moon or Mars, and the gravitational force between two masses.
Electricity
- Electricity cost calculator
Electricity cost of running an appliance per hour, day, month and year, from its wattage, hours of use and your price per kWh (unit).
- Ohm's law calculator
Ohm's law calculator: enter any two of voltage, current, resistance and power to get the other two, shown in the units you pick (mA, kΩ…).
- Resistor colour code calculator
Resistor colour code calculator for 4, 5 and 6-band resistors: colours to ohms and tolerance, or a value to its bands, snapped to E12, E24 or E96.
- RC time constant and RLC circuit calculator
RC and RL time constant and the time to charge or discharge to any percent; series RLC resonant frequency, impedance, phase, Q factor and bandwidth.
- Series and parallel resistor calculator
Series and parallel resistor calculator: total resistance of any number of resistors, plus capacitors or inductors in series or parallel.
- Voltage divider and LED resistor calculator
Voltage divider output, or R1 or R2 for a target voltage; the current-limiting resistor for LEDs with its nearest E12 value and power rating.
- Voltage drop and AWG wire gauge calculator
Voltage drop over a DC, single-phase or three-phase cable run, plus AWG wire size to diameter, mm², kcmil and resistance per km, and back.
Waves & optics
- Thin lens, mirror and Snell's law calculator
Thin lens and mirror equation for image distance, object distance or focal length, with magnification; Snell's law refraction and critical angle.
- Wavelength, frequency and photon energy calculator
Convert wavelength to frequency and photon energy, or back, with c = fλ and E = hf, and see where the wave sits in the electromagnetic spectrum.
Heat & gases
- Ideal gas law calculator
Solve the ideal gas law PV = nRT for pressure, volume, moles or temperature in any units, or find a new state with the combined gas law.
- Specific heat, latent heat and Carnot efficiency calculator
Heat energy from Q = mcΔT (solve for heat, mass, final temperature or specific heat), latent heat Q = mL for melting or boiling, and Carnot efficiency.
Chemistry
- Dilution and molarity calculator
Solve C₁V₁ = C₂V₂ for any dilution variable, get molarity, % w/v and ppm from a weighed mass, the mass to weigh for a solution, or molality.
- Molar mass calculator
Molar mass in g/mol and mass percent composition of any chemical formula, with brackets and hydrates such as CuSO4·5H2O, from IUPAC 2021 atomic weights.
- pH calculator for acids, bases and buffers
Calculate pH, pOH, [H⁺] and [OH⁻] from a concentration, a strong acid or base, a weak acid's Ka or pKa, or a Henderson–Hasselbalch buffer.
- Grams to moles and stoichiometry calculator
Convert grams to moles and particles for any chemical formula, and find the limiting reagent, theoretical yield and leftover excess of a balanced reaction.
Nuclear & space
- Astronomy calculator: light time, magnitudes and redshift
Light travel time for any distance, apparent and absolute magnitude from the distance modulus, and redshift to recession velocity (relativistic Doppler).
- Half-life and radioactive decay calculator
Half-life calculator: amount left, starting amount, elapsed time or half-life from N = N₀·2^(−t/t½), with carbon-14 and other isotope presets.
Lab data
Choosing a calculator: Science
Which physics calculator should I start with?
Start from the quantities you know and the model's assumptions: the kinematics calculator assumes constant acceleration, and Ohm's law describes a simple resistor circuit. If the real system breaks those assumptions, more displayed precision will not make the answer more accurate.
Which calculator do I use for solution concentration?
Use the dilution and concentration calculator, and keep concentration distinct from the amount of substance. For the mass of one mole of a compound, use the molar mass calculator.
Why does my answer have the wrong unit?
A result in the wrong unit usually means a missing factor or a value typed into the wrong field, so check the worked steps for units as well as numbers. Enter consistent units, and keep mass distinct from force and power distinct from energy.