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

Energy and Work

Momentum and Impulse

Projectile Motion

Rotational Motion

Oscillations and Vibrations

Waves and Optics

Automotive Physics

Electronics and Signal Processing

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

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

Aerospace & Space Physics

Astrophysics & Cosmology

Relativity

Quantum Physics

Advanced Optics

Acoustics & Sound

Experimental Physics