Physics
Free physics calculators covering mechanics, thermodynamics, electricity, and waves. Solve force, energy, velocity, and circuit problems in seconds.
Kinematics and Motion
Forces and Newton's Laws
Centripetal Force Calculator – Circular Motion Force
Calculate centripetal force for circular motion from mass, velocity, and radius. Returns force in Newtons, kilonewtons, and lbf with multi-unit input support.
Centrifugal Force Calculator – Linear and Angular Velocity
Calculate centrifugal force and centripetal acceleration from mass, radius, and linear or angular velocity. Supports kg, g, lb, m, cm, ft, m/s, km/h, RPM.
Energy and Work
Elastic Potential Energy Calculator – Spring Energy Formula
Calculate elastic potential energy, spring constant, or displacement using U = ½kx². Solve any Hooke's Law spring variable for physics and engineering problems.
Bullet Energy Calculator – Muzzle Energy & Momentum
Bullet energy calculator: enter weight in grains and velocity in fps to instantly get muzzle kinetic energy in ft-lb and momentum for any cartridge.
Thermal Energy Calculator – Heat, Phase Change & Power
Calculate thermal energy using Q=mcΔT. Find heat for phase changes, heating time from power, and electrical energy. Free online physics tool.
Momentum and Impulse
Projectile Motion
Rotational Motion
Angular Acceleration Calculator
Compute angular acceleration α in rad/s² from velocity change, applied torque, or linear acceleration and radius. Three physics formulas in one free calculator.
Angular Displacement Calculator – Radians and Degrees
Find angular displacement in radians and degrees using θ = (ω₀+ω)/2 × t or θ = ω₀t + ½αt². Supports both kinematic methods for rotational motion problems.
Oscillations and Vibrations
Waves and Optics
Blackbody Radiation Calculator – Wien & Stefan-Boltzmann
Blackbody radiation calculator: find peak wavelength (Wien's law), total emitted power (Stefan-Boltzmann), and Planck spectral radiance for any temperature.
Bragg's Law Calculator – X-ray Diffraction & Crystal Spacing
Bragg's Law calculator: solve nλ = 2d sin θ for X-ray wavelength, crystal plane spacing, Bragg angle, or diffraction order in crystallography.
Brewster's Angle Calculator – Polarization Angle
Brewster's angle calculator: enter refractive indices to find the angle where reflected light is perfectly polarized using Brewster's Law tan(θ)=n₂/n₁.
Diffraction Grating Calculator – Angle, Wavelength & Spacing
Calculate diffraction angle, wavelength, or grating spacing using d·sin(θ)=mλ. Supports any order and groove density for optics, spectroscopy, and physics.
Diopter Calculator – Lens Power & Focal Length Converter
Convert focal length to diopters or diopters to focal length instantly. Supports m, cm, mm, inches and multi-lens combinations for optics and eyewear.
Automotive Physics
Car Jump Distance Calculator – Projectile Motion
Calculate jump distance, flight time, and max height for a car from launch speed, angle, and ramp height using projectile motion. Supports m/s, km/h, and mph.
Car Crash Calculator – Inelastic Collision Physics
Analyse car crashes using conservation of momentum. Compute final velocity, energy lost, and impulse for inelastic collisions. Supports kg, lb, m/s, km/h, mph.
Car Center of Mass Calculator – 3D Vehicle CG
Calculate the 3D centre of gravity of any vehicle. Add components with masses and coordinates for precise vehicle dynamics, motorsport, and safety analysis.
Angle of Banking Calculator – Banked Curve Design
Angle of banking calculator: solve for banking angle, safe speed, or curve radius using tan(θ) = v²/(rg). Covers roads, racetracks, railways, and velodromes.
Electronics and Signal Processing
Watt Converter
Convert watts, kilowatts, megawatts, horsepower, BTU per hour, calories per second, and more with accurate power-unit factors.
EIRP Calculator – Effective Isotropic Radiated Power
Calculate EIRP from transmitter power, cable loss, and antenna gain for RF and satellite links. Returns dBm, dBW, and watts for regulatory and link-budget work.
Special Applications
Material Properties & Engineering
Angle of Repose Calculator – Granular Material Slope
Angle of repose calculator: find the stable slope angle for sand, coal, grain, and bulk solids using internal friction coefficient, particle size, and moisture.
Angle of Twist Calculator – Shaft Torsion
Calculate the angle of twist for circular shafts under torsional load using θ = TL/(GJ). Enter torque, length, shear modulus, and diameter or polar moment.
Brinell Hardness Number Calculator – Material Testing
Brinell hardness calculator: enter load, ball diameter, and indentation diameter to compute BHN using BHN = 2F/(π·D·(D−√(D²−d²))) for metals and alloys.
Buckling Calculator – Euler Critical Load & Stress
Calculate critical buckling load, buckling stress, and safety factor using Euler's formula. Supports fixed, pinned, and cantilever end conditions.
Bulk Modulus Calculator – Material Compressibility
Calculate bulk modulus and compressibility using pressure-volume data, density and sound speed, or Young's modulus and Poisson's ratio for any material.
Density Calculator – Mass, Volume and Density Formula
Calculate density, mass, or volume using ρ = m/V. Supports multiple units for physics, chemistry, engineering, and material science applications.
Elastic Constants Calculator – Young's, Shear & Bulk Modulus
Derive Young's modulus, shear modulus, bulk modulus and Poisson's ratio from any two elastic constants. Essential for material science and engineering.
Specific Gravity Calculator – Density Ratio & Buoyancy
Calculate specific gravity and density ratio relative to water. Enter substance mass and volume, or input density directly, to instantly find buoyancy force.
Thermal Stress Calculator – Strain & Constrained Expansion
Calculate thermal stress σ=EαΔT and biaxial stress for constrained materials. Supports steel, aluminum, copper. Essential for structural engineering.
Von Mises Stress Calculator – Yield & Safety Analysis
Calculate von Mises equivalent stress and factor of safety from normal and shear stress components. Essential for structural and FEA yield analysis.
Mechanical Engineering
Torsional Stiffness Calculator – Shear Stress and Torque
Calculate torsional stiffness, maximum shear stress, polar moment of inertia, and strain energy for circular shafts using shear modulus and geometry.
Transmission Calculator – Signal Power and Data Rate
Calculate free-space path loss, received signal power, SNR, Shannon capacity, and bandwidth efficiency for wireless and satellite communication links.
Electrical Engineering
Electric Field Particle Acceleration Calculator
Electric field acceleration: compute F=qE, a=qE/m, final velocity, and kinetic energy for charged particles — electrons, protons, and ions.
AC Wattage Calculator – Real, Apparent & Reactive Power
AC wattage calculator: enter voltage, current, and power factor to instantly compute real power (W), apparent power (VA), reactive power (VAR), and phase angle.
Capacitance Calculator – Capacitor Values and Energy
Capacitance calculator: find capacitance, stored energy, and electric field for parallel plate, spherical, cylindrical, and series/parallel combinations.
Capacitive Reactance Calculator – Xc Formula
Calculate capacitive reactance (Xc) for any frequency and capacitance using Xc = 1/(2πfC). Free online AC circuit analysis tool for electronics engineers.
Conductivity to Resistivity Calculator – Convert σ to ρ
Conductivity to resistivity calculator: convert electrical conductivity (S/m) to resistivity (Ω·m) via ρ = 1/σ for conductors, semiconductors, and insulators.
Delta to Wye Conversion Calculator – Resistor Network
Convert Delta (Δ) and Wye (Y) resistor networks instantly. Enter three resistance values and get the equivalent configuration for circuit analysis and design.
Dipole Moment Calculator – Electric Dipole Moment Online
Calculate electric dipole moment from charge and separation in C·m and Debye. Shows x/y vector components for molecular polarity and electric field interaction.
Electrical Power Calculator – P = VI, I²R, V²/R
Calculate electrical power from voltage and current, voltage and resistance, or current and resistance. Covers all three power formulas for circuit design.
Electric Field Calculator – E, Force & Potential
Calculate electric field strength, electrostatic force, and electric potential with Coulomb's law. Useful for physics study, labs, and engineering checks.
Electric Motor Torque Calculator – Power, RPM & Torque
Calculate electric motor torque from power and speed, or solve for power or RPM. Supports kW/Nm and HP/ft·lb for industrial and engineering applications.
Electric Potential Calculator – Charge & Distance
Calculate electric potential, charge, or distance using V = kQ/r. Ideal for electrostatics, physics homework, and circuit voltage estimation.
Voltage Drop Calculator
Calculate voltage drop in electrical wire runs from current, length, and resistance. Find voltage drop percentage and power loss for safe wiring.
Volt to Electron Volt Calculator
Convert voltage to electron volts (eV) and joules instantly. Essential for physics, electronics, and quantum mechanics calculations.
VSWR Calculator – Voltage Standing Wave Ratio
Calculate VSWR, return loss, mismatch loss, and transmission efficiency from power or impedance measurements for RF transmission line analysis.
Watt Calculator
Calculate volts, amps, ohms, watts, and optional watt-hours by entering any two electrical values, then solve the rest for quick circuit checks.
Watt Hour Calculator
Calculate daily watt-hours, monthly kilowatt-hours, and electricity cost from appliance wattage, usage time, monthly days, and utility rate.
Watts to Amps Calculator
Convert watts to amps from power, voltage, and optional power factor for DC or AC loads so you can size circuits and compare current draw.
Electronic Circuits
Boost Converter Calculator – DC-DC Step-Up Voltage Design
Boost converter calculator: find duty cycle, inductor ripple, peak current, and power for DC-DC step-up circuits in power electronics design.
Breaker Size Calculator – Wire Gauge & Circuit Breaker
Circuit breaker size calculator: enter voltage, power, power factor, and load type to find required breaker amperage and NEC wire gauge instantly.
Bridge Rectifier Calculator – AC to DC Conversion
Bridge rectifier calculator: enter AC voltage, load, diode drop, frequency, and capacitance to compute DC output, ripple voltage, ripple factor, and PIV.
Buck Converter Calculator – DC-DC Step-Down Design
Calculate duty cycle, inductor ripple current, and output ripple voltage for DC-DC buck converters. Design efficient step-down power supplies quickly.
Capacitive Transformerless Power Supply Calculator
Design capacitive transformerless supplies: compute drop capacitor reactance, DC load current, and zener dissipation for low-power LED circuits.
Capacitor Charge Time Calculator – RC Circuit
Calculate capacitor charging time in RC circuits using t = −RC × ln(1 − Vc/Vs). Find the RC time constant and voltage milestones for electronics timing design.
Capacitor Calculator – Charge, Voltage, and Plate Geometry
Capacitor calculator: find charge, capacitance, or voltage using Q = CV, or calculate parallel-plate capacitance from geometry and dielectric constant.
Capacitor Energy Calculator – Stored Energy E = ½CV²
Calculate energy stored in a capacitor using E = ½ × C × V². Instant joules result for electronics, power systems, and electrical engineering.
Capacitors in Series Calculator – Equivalent Capacitance
Calculate equivalent capacitance, voltage distribution across each capacitor, charge, and energy stored for up to four capacitors connected in series.
Capacitor Size Calculator – Dimensions & Energy Storage
Calculate plate area, energy stored, and power density for a capacitor from capacitance, voltage, and dielectric constant. Perfect for electronics design.
Dipole Antenna Calculator – Length, Wavelength & Impedance
Calculate dipole antenna total length, arm size, and impedance for any frequency. Supports half-wave and quarter-wave designs with customisable velocity factor.
Ohm's Law Calculator for Voltage, Current, Resistance
Ohm's Law calculator: enter any two of voltage, current, resistance, or power to instantly solve the rest using V=IR and P=VI for circuit design.
Three Phase Power Calculator – Voltage & Current
Calculate three-phase apparent, active, and reactive power from voltage, current, and power factor. Essential tool for electrical engineers.
Transformer Sizing Calculator – Required kVA Rating
Calculate the required transformer kVA rating from load power, power factor, efficiency, temperature, and safety factor for reliable electrical system design.
Transistor Biasing Calculator – DC Operating Point
Calculate transistor DC operating point, collector current, voltage gain, and stability factor for voltage divider bias circuits. Ideal for amplifier design.
Voltage Divider Calculator
Calculate output voltage, current, and power dissipation for resistor voltage divider circuits. Essential for electronics engineers and students.
Voltage Regulation Calculator
Calculate load regulation and line regulation for power supplies. Determine voltage stability from no-load and full-load voltage values.
Wheatstone Bridge Calculator – Measure Unknown Resistance
Calculate unknown resistance using the Wheatstone bridge circuit. Enter R1, R2, R3, voltage ratio, and supply voltage for precise resistance measurement.
Fluid Mechanics
Broad Crested Weir Calculator – Discharge & Flow
Broad crested weir calculator: enter width, upstream head, Cd, and Manning's n to calculate discharge, critical depth, and flow regime for open-channel design.
Buoyancy Calculator – Buoyant Force & Floating Conditions
Buoyancy calculator: compute buoyant force, net force, and floating or sinking conditions using Archimedes' principle with mass, volume, and fluid density.
Darcy's Law Calculator for Porous Media Flow Rate
Calculate volumetric flow rate, Darcy velocity, and seepage velocity through porous media using Darcy's Law for groundwater and reservoir engineering.
Darcy-Weisbach Friction Loss Calculator for Pipe Flow
Calculate pipe friction head loss, Reynolds number, and friction factor using the Darcy-Weisbach equation for hydraulic engineering and fluid mechanics.
Differential Pressure Calculator
Calculate differential pressure across valves, filters, and pipes. Includes dynamic pressure from fluid density and flow velocity for HVAC and engineering.
Water Density Calculator – Temperature, Salinity & Pressure
Calculate water density from temperature, salinity, and pressure using the UNESCO equation. Compare measured vs theoretical density for fresh and saltwater.
Water Viscosity Calculator
Calculate water dynamic viscosity, kinematic viscosity, density, and Reynolds number from temperature, pressure, flow velocity, and pipe size fast.
Wind Correction Angle Calculator – Aviation Navigation
Calculate wind correction angle, true heading, and ground speed. Essential aviation tool for pilots to compensate for wind drift accurately.
Wind Load Calculator – Wind Pressure and Force on Structures
Calculate wind load, dynamic pressure, and wind force on structures. Essential tool for structural engineers using wind speed, dimensions, and exposure factors.
Thermodynamics & Heat Transfer
Boltzmann Factor Calculator for Statistical Physics
Boltzmann factor calculator: compute e^(−E/kT), thermal energy kT, and state occupation probabilities for statistical mechanics and thermodynamics.
Boyle's Law Calculator – Gas Pressure and Volume
Boyle's Law calculator: solve P₁V₁ = P₂V₂ for any unknown gas pressure or volume at constant temperature. Ideal for chemistry and physics problems.
BTU to Tons Converter – HVAC & Refrigeration
Convert BTU per hour to refrigeration tons instantly for HVAC and cooling system design. Shows kilowatt and horsepower equivalents for easy comparison.
Calorimetry Calculator – Heat Energy & Temperature Change
Calorimetry calculator: compute heat energy using Q=mcΔT plus optional phase-change heat. Ideal for chemistry labs, thermodynamics, and heat transfer analysis.
Carnot Efficiency Calculator – Max Thermodynamic Efficiency
Calculate the maximum theoretical Carnot efficiency for any heat engine from hot and cold reservoir temperatures in Kelvin using η = 1 − Tc/Th.
Combined Gas Law Calculator – Solve P₁V₁/T₁ = P₂V₂/T₂
Combined Gas Law calculator: enter five of six gas variables (pressure, volume, temperature) and instantly solve for the unknown using P₁V₁/T₁ = P₂V₂/T₂.
Compressibility Factor Calculator – Z-Factor for Real Gases
Compressibility factor (Z-factor) calculator for real gases: enter pressure, temperature, and critical properties to quantify deviation from ideal gas behavior.
NTU Effectiveness Calculator – Heat Exchanger Analysis
Calculate NTU and heat exchanger effectiveness from temperatures, flow rates, and UA. Analyze thermal performance and identify fouling in industrial systems.
Efficiency Calculator – Energy, Power & System Efficiency
Calculate efficiency ratios, energy losses, and power conversion rates for motors, heat engines, and electrical systems. Compare results against design specs.
Specific Gas Constant Calculator – R Value for Any Gas
Calculate the specific gas constant (R) for any gas from its molar mass. Use the ideal gas law PV=mRT to solve for pressure, volume, temperature, or mass.
Specific Heat Calculator – Q = m × c × ΔT Formula
Calculate heat energy Q, specific heat capacity, or temperature change using Q = m × c × ΔT. Perfect for thermodynamics, engineering, and lab applications.
Thermal Equilibrium Calculator – Final Temperature & Heat
Find equilibrium temperature when two objects mix using Q=mcΔT. Calculate heat transferred and conduction heat flow for thermal balance problems.
Thermal Expansion Calculator – Linear, Area & Volume
Calculate thermal expansion for steel, aluminum, copper and more. Supports linear, area, and volume expansion using ΔL=αL₀ΔT. Essential for engineering.
Thermal Resistance Calculator – Heat Flow & R-Value
Calculate thermal resistance R=L/(kA), heat flow rate, temperature gradient, and R-value for insulation design and heat transfer engineering.
Water Heating Calculator – Energy, Time & Cost
Calculate energy, heating time, cost, and CO₂ emissions to heat water. Supports liters and gallons, electric and heat pump systems.
Atmospheric & Weather Physics
Air Density Calculator – Temperature, Pressure & Humidity
Air density calculator: compute atmospheric air density from temperature, pressure, and humidity using the ideal gas law with vapour pressure correction.
Air Pressure at Altitude Calculator
Air pressure at altitude calculator: compute atmospheric pressure, temperature, air density, and density altitude using the barometric formula and ISA model.
Density Altitude Calculator – Aviation Performance Tool
Calculate density altitude and air density from pressure altitude, temperature, and humidity. Essential aviation tool for aircraft performance planning.
Dew Point Calculator – Condensation & Humidity
Calculate dew point temperature from air temperature and relative humidity using the Magnus formula. Essential for weather, HVAC, and condensation analysis.
Aerospace & Space Physics
Alien Civilization Calculator – Drake Equation
Drake Equation calculator: estimate civilizations in the Milky Way using star formation rate, planet fractions, life probability, and civilisation lifespan.
BMEP Calculator – Brake Mean Effective Pressure
BMEP calculator: compute brake mean effective pressure, engine power in kW and hp, and specific output from torque and displacement for any 4-stroke engine.
Carburetor CFM Calculator – Engine Air Flow Sizing
Calculate required carburetor CFM from engine displacement, RPM, and volumetric efficiency. Size your carb correctly for peak performance and fuel economy.
Delta-V Calculator – Tsiolkovsky Rocket Equation
Calculate delta-v using the Tsiolkovsky rocket equation. Enter initial mass, final mass, and exhaust velocity for orbital maneuver and mission planning.
Specific Impulse Calculator – Rocket Engine Efficiency
Calculate specific impulse (Isp) and effective exhaust velocity for rocket engines. Enter thrust and mass flow rate to measure propulsion efficiency in seconds.
Thrust to Weight Ratio Calculator – Aerospace Performance
Calculate thrust-to-weight ratio (TWR), net force, and net acceleration for rockets, aircraft, and drones. Instantly determine if your vehicle can lift off.
Wing Loading Calculator – Stall Speed and Performance
Calculate aircraft wing loading and stall speed from weight and wing area. Supports metric and imperial units for aircraft, gliders, and RC models.
Astrophysics & Cosmology
Black Hole Collision Calculator – Merger & GW Energy
Black hole collision calculator: compute merger time, chirp mass, gravitational wave energy, and final Schwarzschild radius for binary black hole systems.
Black Hole Temperature Calculator – Hawking Radiation
Black hole temperature calculator: compute Hawking radiation temperature, Schwarzschild radius, emitted power, and evaporation time from any black hole mass.
Relativity
Bug-Rivet Paradox Calculator – Special Relativity
Explore the Bug-Rivet Paradox of special relativity. Calculate Lorentz factor, length contraction, time dilation, and relativistic kinetic energy at any speed.
Time Dilation Calculator – Einstein's Special Relativity
Calculate relativistic time dilation using Einstein's special relativity. Enter velocity and proper time to find dilated time and Lorentz factor.
Warp Speed Calculator – Star Trek Warp Factor
Calculate warp speed multiplier, travel time, and energy for any Star Trek warp factor. Fun physics tool for sci-fi fans and educators.
Quantum Physics
Bohr Model Calculator – Electron Energy & Orbit Radius
Bohr model calculator: compute electron energy levels, orbital radius, velocity, and de Broglie wavelength for any atom using the Bohr atomic model.
Compton Scattering Calculator – Wavelength Shift & Energy
Compton scattering calculator: enter photon energy and angle to compute wavelength shift, scattered photon energy, and electron recoil energy transfer.
Compton Wavelength Calculator – Particle Quantum Scale
Compton wavelength calculator: compute λ = h/(mc) for electrons, protons, neutrons, and custom particle masses using Planck's constant and the speed of light.
De Broglie Wavelength Calculator – Wave-Particle Duality
Calculate the De Broglie wavelength from mass and velocity, kinetic energy, or momentum. Reveals wave-particle duality in nanometres and picometres.
Wien's Law Calculator – Peak Wavelength from Temperature
Calculate the peak wavelength of blackbody radiation from temperature using Wien's displacement law. Perfect for physics, astronomy, and thermal analysis.
Advanced Optics
Speed of Light Calculator – Time, Distance & Speed in Media
Calculate travel time, distance, or speed of light in any medium using refractive index. Supports vacuum, water, glass, and custom media for physics and optics.
Thin Film Optical Coating Calculator – AR & HR
Calculate reflectance and transmittance of single-layer thin film coatings using Fresnel equations. Analyze AR and HR coatings for s- and p-polarizations.
Thin Lens Equation Calculator – Focal Length
Solve the thin lens equation for focal length, object, or image distance. Find magnification and identify real, virtual, upright, or inverted images.
Acoustics & Sound
Acoustic Impedance Calculator – Reflection & Transmission
Acoustic impedance Z=ρc: compute reflection, transmission coefficients, and intensity percentages for sound waves at a boundary between two media.
Alfvén Velocity Calculator – MHD Wave Speed in Plasma
Alfvén velocity calculator: compute MHD wave speed in plasma from magnetic field strength, ion density, and ion mass using the formula v_A = B / √(μ₀ ρ).
Decibel (dB) Calculator – Convert Ratios and Combine Sources
Convert power or amplitude ratios to dB, dB back to ratios, or combine multiple decibel sources. Covers acoustics, electronics, and signal processing formulas.
dB Gain Calculator for Power and Voltage Amplification
Calculate dB gain between input and output, or find the unknown output or input from a specified gain. Supports power and voltage for RF design.
Experimental Physics
Blast Radius Calculator – Overpressure & Safety Distances
Blast radius calculator: compute explosion overpressure, fireball radius, danger zone, and safe distance from TNT yield using Hopkinson-Cranz scaling.
Buoyancy Experiment Calculator – Float, Sink, or Neutral
Buoyancy experiment calculator: find buoyant force, object density, and predict float, sink, or neutral buoyancy using Archimedes' principle for physics labs.
Electrical Mobility Calculator – Drift Velocity & Field
Calculate carrier mobility, drift velocity, or electric field using μ = v_d/E. Essential for semiconductor physics, device design, and materials research.
Volume to Mass Calculator
Calculate mass from volume and density with unit selection. Perfect for engineering, chemistry, and material science applications.