Science tools
Chemistry, physics, biology and astronomy calculators — every formula worked from first principles, with the assumptions spelled out.
Most popular
Chemical Equation Balancer
Balance any chemical equation to whole numbers.
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Force Calculator (F = ma)
Solve Newton's second law for force, mass or acceleration.
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Ideal Gas Law Calculator (PV = nRT)
Solve for pressure, volume, moles or temperature.
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Kinematics Calculator (SUVAT)
Solve motion problems from any three of u, v, a, t, s.
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Kinetic & Potential Energy Calculator
KE = ½mv², PE = mgh and total mechanical energy.
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Molar Mass Calculator
Molar mass and percent composition from a formula.
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Mole Calculator (grams ↔ moles ↔ particles)
Convert between mass, moles and number of particles.
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Percent Error Calculator
Percent error against a true value, or percent difference.
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Projectile Motion Calculator
Range, height, flight time and the trajectory curve.
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Punnett Square Calculator
Genotype and phenotype ratios of a cross.
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Radioactive Decay & Half-Life Calculator
Amount remaining, activity and radiometric dating.
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Weight on Other Planets Calculator
Your weight across the solar system.
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pH Calculator
pH, pOH and ion concentrations for acids and bases.
Chemistry
Chemical Equation Balancer
Balance any chemical equation to whole numbers.
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Ideal Gas Law Calculator (PV = nRT)
Solve for pressure, volume, moles or temperature.
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Molar Mass Calculator
Molar mass and percent composition from a formula.
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Mole Calculator (grams ↔ moles ↔ particles)
Convert between mass, moles and number of particles.
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pH Calculator
pH, pOH and ion concentrations for acids and bases.
Boiling & Freezing Point Calculator
Boiling-point rise and freezing-point drop of solutions.
Calorimetry Calculator (Q = mcΔT)
Heat, mass, specific heat or temperature change.
Concentration Converter
Molarity ↔ g/L ↔ ppm ↔ percent (w/v).
Dilution Calculator (C₁V₁ = C₂V₂)
Solve any term of the dilution equation.
Electron Configuration Calculator
Aufbau configuration and noble-gas shorthand.
Empirical & Molecular Formula Calculator
Formula from percent composition or masses.
Equilibrium (ICE Table) Solver
Equilibrium concentrations from K and initial amounts.
Nernst Equation Calculator
Cell potential away from standard conditions.
Periodic Table Element Lookup
Atomic data for any element by symbol, name or number.
Reaction Rate & Kinetics Calculator
Integrated rate laws, half-life and Arrhenius.
Stoichiometry Calculator
Amounts of every species from one known amount.
Physics: Mechanics
Force Calculator (F = ma)
Solve Newton's second law for force, mass or acceleration.
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Kinematics Calculator (SUVAT)
Solve motion problems from any three of u, v, a, t, s.
popular
Kinetic & Potential Energy Calculator
KE = ½mv², PE = mgh and total mechanical energy.
popular
Projectile Motion Calculator
Range, height, flight time and the trajectory curve.
Circular Motion Calculator
Centripetal acceleration, force and angular speed.
Density Calculator (ρ = m/V)
Solve density, mass or volume from the other two.
Free Fall Calculator
Fall time and impact speed from a height, or vice versa.
Friction & Inclined Plane Calculator
Normal force, friction and whether it slides.
Momentum & Collision Calculator
One-dimensional elastic and inelastic collisions.
Pendulum & Spring Period Calculator
Period and frequency of a pendulum or a spring.
Pressure & Buoyancy Calculator
Fluid pressure with depth and Archimedes buoyancy.
Torque Calculator
Turning effect of a force, τ = r·F·sinθ.
Work & Power Calculator
Work from force and distance, and the power to do it.
Physics: Waves & Modern
Percent Error Calculator
Percent error against a true value, or percent difference.
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Radioactive Decay & Half-Life Calculator
Amount remaining, activity and radiometric dating.
Coulomb's Law Calculator
Electrostatic force between two charges.
Doppler Effect Calculator
Observed frequency for a moving source or observer.
Error Propagation Calculator
Combine measurement uncertainties through a formula.
Lens & Mirror Equation Calculator
Image distance and magnification from 1/f = 1/dₒ + 1/dᵢ.
Photon Energy Calculator (E = hf)
Energy, frequency and wavelength of a photon.
Snell's Law & Refraction Calculator
Refraction angle, critical angle and total reflection.
Special Relativity Calculator
Time dilation, length contraction and E = mc².
Wavelength ↔ Frequency Converter
λ = v / f for light, sound or any wave speed.
de Broglie Wavelength Calculator
The wavelength of a moving particle.
Astronomy & Space
Weight on Other Planets Calculator
Your weight across the solar system.
Astronomical Distance Converter
Light-years, parsecs, AU and light travel time.
Escape & Orbital Velocity Calculator
Escape speed, orbit speed and period.
Newton's Law of Gravitation Calculator
Gravitational force between two masses.
Telescope Calculator
Magnification, f-ratio, resolution and exit pupil.
Biology
Punnett Square Calculator
Genotype and phenotype ratios of a cross.
Aquarium Stocking & Cycling Calculator
Bioload-based stocking level and a fishless cycling plan.
Bacterial Growth Calculator
Population from doubling time and elapsed time.
DNA & RNA Sequence Toolkit
Complement, transcription, translation and GC content.
Hardy-Weinberg Equilibrium Calculator
Allele and genotype frequencies in a population.
Michaelis-Menten Kinetics Calculator
Enzyme reaction rate from Vmax, Km and [S].
About these tools
Science calculators spanning chemistry, physics, biology and astronomy: molar mass, solution dilution, ideal gas law, projectile motion, half-life decay, kinematics and orbital mechanics. Each calculator states the equation and assumptions it relies on, making it a dependable companion for homework, lab work and curiosity.