Free Physics Calculators

Velocity Calculator — Speed & Time

Calculate velocity, distance, or time using v = d/t.

Acceleration Calculator — Kinematic Equations

Solve for acceleration, final velocity, initial velocity, time, or displacement using the five kinematic equations. Includes g-force conversion and step-by-step working.

Force Calculator — Newton's Second Law F = ma

Calculate force, mass, or acceleration using Newton's Second Law (F = ma). Solve for any variable with multi-unit support (N, kN, lbf, kgf, kg, lb, slug), preset real-world scenarios, g-force output, and gravitational weight on seven Solar System bodies.

Projectile Motion Calculator

Calculate range, max height, time of flight, and trajectory.

Work & Energy Calculator

Calculate work done, kinetic energy, potential energy, and power.

Momentum Calculator — p=mv

Calculate momentum, impulse, and solve collision problems.

Ohm's Law Calculator — V=IR

Calculate voltage, current, resistance, or power using Ohm's law.

Wave Calculator — Wavelength & Frequency

Calculate wavelength, frequency, period, and wave speed.

Gravity Calculator — Free Fall, Force & Escape

Calculate free fall height, time, and velocity. Compute gravitational force with Newton's law. Find surface gravity and escape velocity for any planet. NASA planet data included.

Ideal Gas Law Calculator — PV=nRT

Solve PV = nRT for any unknown variable.

Friction Calculator — Static, Kinetic & Inclined Plane

Calculate static and kinetic friction forces, find the normal force or coefficient, and solve inclined plane problems. Includes 11 material presets with published μ values.

Pendulum Calculator — Period & Frequency

Calculate the period, frequency, and length of a simple pendulum.

Spring Constant Calculator — Hooke's Law

Calculate spring constant, force, or displacement using Hooke's law (F = kx).

Coulomb's Law Calculator — Electrostatic Force

Calculate electrostatic force, charge, or distance using Coulomb's Law F = kq₁q₂/r². Supports multiple units, dielectric media, and solve-for-any-variable mode.

Capacitance Calculator — Q=CV, Energy & RC Circuits

Calculate charge, voltage, energy stored, series/parallel equivalents, and RC time constants for capacitors. Multi-unit support with circuit diagrams.

Thermal Expansion Calculator

Calculate linear and volumetric thermal expansion of materials.

Pressure Calculator — P=F/A

Calculate pressure from force and area, convert pressure units, and compute fluid pressure.

Density Calculator — ρ = m/V, Mass & Volume

Calculate density, mass, or volume using ρ = m/V. Supports multi-unit inputs, 40+ material presets, specific gravity, buoyancy check, and full unit conversion table.

Decibel Calculator — dB, Power & Sound Level

Convert between decibels, power ratios, and amplitude ratios. Combine multiple sound sources, compute distance attenuation, and see NIOSH hearing safety limits with an SPL reference meter.

Doppler Effect Calculator — Sound & Light

Calculate observed frequency shift for sound and light using classical and relativistic Doppler formulas. Includes medium presets, direction toggles, semitone output, and redshift z.

Centripetal Force Calculator

Solve for centripetal force, mass, velocity, or radius for circular motion. Supports linear velocity, angular velocity, frequency, and period. Includes 5 real-world presets, g-force output, and circular motion diagram.

Torque Calculator — τ = rF sin(θ)

Calculate torque from force, distance, and angle of application.

Kinetic Energy Calculator — KE=½mv²

Calculate translational and rotational kinetic energy.

Potential Energy Calculator — PE=mgh

Calculate gravitational potential energy (mgh) and elastic potential energy (½kx²).

Snell's Law Calculator — Refraction

Calculate refraction angles and critical angles for light passing between media.

Lens Equation Calculator — Optics

Calculate focal length, object distance, image distance, and magnification for thin lenses.

Half-Life Calculator — Radioactive Decay

Calculate remaining quantity, time elapsed, half-life, and decay constant using the exponential decay formula. Supports 4 modes, decay table, and isotope reference.

Escape Velocity Calculator — Planets & Stars

Calculate escape velocity, orbital speed, surface gravity, Schwarzschild radius, and orbital period for any planet, star, or celestial body. Solve for velocity, mass, or radius with solar system presets.

Buoyancy Calculator — Archimedes

Calculate buoyant force using Archimedes' principle (F = ρVg). Determines float or sink status, fraction submerged, apparent weight, net force, and operating leverage across Earth, Moon, Mars, and Jupiter gravity. Includes fluid and material density presets.

Heat Transfer Calculator — Conduction, Convection & Radiation

Calculate heat transfer by Fourier conduction, Newton convection, Stefan-Boltzmann radiation, or Q=mcΔT sensible heat. Material presets, NIST constants, step-by-step working.

Electric Power Calculator — P=VI, V²/R & I²R

Calculate electric power from any two of voltage, current, and resistance. Includes energy consumption in kWh and electricity cost estimation with preset appliances.

Magnetic Force Calculator — Lorentz

Calculate the magnetic force on a moving charge (Lorentz force) F = qvB sin(θ).

Resistor Color Code Calculator

Decode 4-band and 5-band resistor color codes to find resistance and tolerance.

Blackbody Radiation Calculator

Calculate peak wavelength, total radiated power per unit area, photon energy, and Planck spectrum for any temperature and emissivity. Visual spectrum chart included.

Reynolds Number Calculator

Calculate the Reynolds number to determine laminar or turbulent fluid flow.

Electric Field Calculator — Point Charge & Plates

Calculate electric field strength from point charges (E = kQ/r²), parallel plates (E = V/d), and electrostatic force (F = qE) with unit conversion and air-breakdown indicator.

Sound Intensity Calculator — dB

Calculate sound intensity level in dB from intensity, and convert between intensity and dB.

Specific Gravity Calculator

Calculate specific gravity, relative density, and compare material density to water.

Wave Speed Calculator — v = fλ

Calculate wave speed, frequency, wavelength, or period using v = fλ. Supports sound, light, and all wave types across different media with unit conversion.

Kinematics Calculator — SUVAT Equations

Solve all five SUVAT kinematic equations for displacement, initial velocity, final velocity, acceleration, and time. Enter any three known values and instantly solve for the remaining two.

Energy Calculator — KE, PE, Thermal & Electrical

Calculate kinetic energy (½mv²), gravitational PE (mgh), elastic PE (½kx²), thermal energy (mcΔT), and electrical energy (Pt). Convert between energy forms and units.

Specific Heat Calculator — Q = mcΔT Calorimetry

Calculate heat energy (Q), mass (m), specific heat capacity (c), or temperature change (ΔT) using Q = mcΔT. Solve any unknown, includes a reference table of 30+ common substances, and supports calorimetry problems with heat exchange between objects.

Combined Gas Law Calculator — P₁V₁/T₁ = P₂V₂/T₂

Solve the combined gas law for any unknown pressure, volume, or temperature. Also handles Boyle's Law (constant T), Charles's Law (constant P), and Gay-Lussac's Law (constant V) as special cases. Supports all major pressure and volume units.