Physics & Chemistry

Half-Life Calculator

Free online half-life calculator for radioactive decay. Calculate remaining quantity, initial quantity, elapsed time, or half-life from any three values.

Horsepower Calculator

Calculate horsepower using force, distance, and time. Free online horsepower calculator with multiple unit support and instant results.

Mass Calculator

Calculate mass from density and volume with unit conversion. Free online mass calculator supporting metric and imperial units with real-time results.

Speed Calculator

Calculate speed, distance, and time with unit conversion. Free online speed calculator for travel planning, physics problems, and everyday calculations.

Molecular Weight Calculator

Calculate molecular weight and molar mass from chemical formulas. Free online molecular weight calculator for chemistry students and professionals.

Density Calculator

Calculate density, mass, or volume using the density formula. Input any two values to find the third with multiple unit options.

Molarity Calculator

Calculate molarity, mass, molecular weight, or volume of a solution. Input any three values to find the fourth using the molarity formula.

Speed Distance Time Calculator

Calculate speed, distance, or time using the formula d = st. Free online speed distance time calculator with instant browser-side results.

Displacement Calculator

Calculate displacement using s=vt, s=ut+½at², and s=½(v+u)t formulas. Free online displacement calculator for physics problems.

E=mc² Calculator

Calculate energy from mass using Einstein E=mc² equation. Free online mass-energy equivalence calculator with step-by-step solutions.

Elastic Potential Energy Calculator

Calculate elastic potential energy, spring constant, or displacement using U = ½kΔx². Free online elastic potential energy calculator with unit conversion and step-by-step solutions.

Force Calculator

Calculate force, mass, or acceleration using Newton's Second Law F = ma. Free online force calculator with unit conversion and step-by-step solutions.

Friction Calculator

Calculate friction force, coefficient of friction, or normal force using the friction equation f = μN. Free online friction calculator with unit conversion and step-by-step solutions.

Gravitational Potential Energy Calculator

Calculate gravitational potential energy, mass, gravity, or height using the PE = mgh formula with multiple unit conversions.

Ideal Gas Law Calculator

Calculate pressure, volume, moles, or temperature using the Ideal Gas Law (PV = nRT) with multiple unit conversions and the universal gas constant R.

Hookes Law Calculator

Calculate spring force, spring constant, displacement, or acceleration using Hookes Law (F = -kx) with multiple unit conversions.

Impulse Calculator

Calculate impulse, force, or time using the J = Ft formula with multiple unit conversions.

Impulse Momentum Calculator

Calculate force, mass, time, or velocity change using the impulse-momentum formula FΔt = mΔv with unit conversions.

Kinetic Energy Calculator

Calculate kinetic energy, mass, or velocity using the KE = ½mv² formula with multiple unit conversions.

Momentum Calculator

Calculate momentum (p=mv), mass, or velocity using the momentum formula. Free online momentum calculator with unit conversions and significant figures.

Pressure Calculator

Calculate pressure (P=F/A), force, or area using the pressure formula. Free online pressure calculator with unit conversions and step-by-step solutions.

Uniformly Accelerated Motion Calculator

Solve kinematic equations for uniformly accelerated motion. Calculate initial velocity, final velocity, displacement, acceleration, and time using standard motion formulas.

Average Velocity Calculator

Calculate average velocity, initial velocity, or final velocity using the formula v̄ = (v + u)/2. Solve for any variable with unit conversions.

Wavelength Calculator

Calculate wavelength, velocity, or frequency using the formula λ = v/f. Solve for any variable with unit conversions including speed of light and sound references.

Weight Calculator

Calculate weight, mass, or gravity using the formula W = mg. Solve for any variable with unit conversions including planetary gravity references.

Work Calculator

Calculate work, force, or displacement using the physics work formula W = Fs. Free online work calculator with unit conversion and step-by-step solutions.

Biot Number

Calculate the Biot number (Bi) for heat transfer analysis. Solve for heat transfer coefficient, characteristic length, or thermal conductivity with our free online Biot number calculator.

Cauchy Number Calculator

Calculate the Cauchy number for fluid flow. Solve for Cauchy number, flow velocity, fluid density, or bulk modulus elasticity using the formula Ca = ρv²/Bₛ.

Centripetal Acceleration Calculator

Calculate centripetal acceleration for circular motion. Solve for acceleration, velocity, or radius using the formula a = v²/r.

Centripetal Force Calculator

Calculate centripetal force for circular motion. Solve for force, mass, velocity, or radius using the formula F = mv²/r.

Circular Motion Calculator

Calculate centripetal acceleration and circular velocity for objects in uniform circular motion. Solve for acceleration, velocity, radius, or period.

Compression Ratio Calculator

Calculate engine static compression ratio from bore, stroke, combustion chamber, head gasket, and piston deck volumes.

Coulomb Law Calculator

Calculate electrostatic force between two point charges. Determine force, charge, or distance with real-time results.

Doppler Effect Calculator

Calculate the Doppler effect frequency shift for moving sources and receivers. Solve for observed frequency, source frequency, receiver velocity, and wave velocity.

Dry Adiabatic Lapse Rate Calculator

Calculate the dry adiabatic lapse rate and temperature at altitude for unsaturated air parcels using thermodynamic formulas.

Seismometer Calculator

Calculate earthquake magnitude using seismometer data. Solve for Richter magnitude, seismic moment, moment magnitude, and seismic energy with our online seismometer calculator.

Eckert Number Calculator

Calculate the Eckert number for fluid flow analysis. Solve for Eckert number, velocity, specific heat, and temperature change with our online Eckert number calculator for viscous dissipation assessment.

Einstein E=mc² Calculator

Calculate mass-energy equivalence using the E=mc² formula. Solve for energy, mass, or speed of light with unit conversions.

Escape Velocity Calculator

Calculate escape velocity, planet mass, or radius using v = √(2GM/R). Free online physics tool for space, rocket, and astrophysics calculations.

Euler Number Calculator

Calculate the Euler number, pressure drop, fluid density, or flow velocity using Eu = Δp / (ρv²). Free online fluid dynamics tool for engineers.

Gravitational Acceleration Calculator

Calculate gravitational acceleration using g = GM/r². Solve for acceleration, planet mass, or distance from center. Find surface gravity on Earth, Mars, Moon, Jupiter and other planets.

Gravitational Force Calculator

Calculate gravitational force using Newton's law of universal gravitation F = Gm\u2081m\u2082/r\u00b2. Solve for force, distance, or either mass with unit conversions and step-by-step solutions.

Kepler's Third Law Calculator

Calculate orbital period, orbital radius, or central body mass using Kepler's third law of planetary motion for any two-body orbit.

Lens and Mirror Equation Calculator

Calculate image distance, object distance, or focal length using the thin lens and mirror equation 1/f = 1/do + 1/di with magnification.

Lightning Distance Calculator

Calculate how far away a lightning strike is using the flash-to-bang method. Count seconds between flash and thunder, get distance instantly.

Moment of Force Calculator

Calculate the moment of force, applied force, or lever arm distance using M = F x d with various unit conversions.

Orbital Period Calculator

Calculate orbital period, orbital radius, or orbital velocity for a circular orbit. Support unit conversions.

Pendulum Calculator

Calculate the period, frequency, length, or gravity for simple and compound physical pendulums.

Percent Yield Calculator

Calculate percent yield, actual yield, or theoretical yield for chemistry experiments.

Power Calculator

Calculate power using four formulas: work over time, force times velocity, voltage times current, and force times displacement over time.

Projectile Motion Calculator

Calculate projectile motion parameters including range, maximum height, time of flight, and velocity components. Free physics projectile calculator.

Radioactive Activity Calculator

Calculate radioactive activity in becquerels and curies using the A = λN formula. Free online radioactivity calculator for physics.

Seismic Geophone Calculator

Calculate subsurface layer depth using seismic refraction survey data. Solve for depth, crossover distance, or layer velocities using t = (d/2)√((v₂-v₁)/(v₂+v₁)).

Snell's Law Calculator

Solve n₁ sin θ₁ = n₂ sin θ₂ for refracted angle, incident angle, or refractive index. Critical-angle and total internal reflection support.

Sound Intensity Decibel Calculator

Calculate sound intensity level in decibels (dB), sound intensity in W/m², or reference intensity in W/m².

Sound Wave Equations Calculator

Solve sound wave properties: wavelength, frequency, velocity, sound intensity level, sound pressure level (SPL), point source intensity, and noise pollution level.

Sound Wave Speed Calculator

Solve v = f × λ for velocity, frequency, or wavelength. Supports m/s, Hz, kHz, MHz, m, cm, ft, and other units.

Specific Gas Constant Calculator

Solve for specific gas constant, universal gas constant, or molecular weight using R = R*/MW. Essential for thermodynamic property calculations.

Specific Gravity Calculator

Calculate specific gravity from density or specific weight ratios. Determine if a substance floats or sinks. Includes material reference values. Free.

Specific Heat Calculator

Calculate heat energy (Q), mass (m), specific heat capacity (c), or temperature change (ΔT) using the Q = mcΔT formula with unit conversion and material reference table.

Specific Volume Calculator

Calculate specific volume (v), volume (V), or mass (m) using v = V/m. Free online specific volume calculator with unit conversion and material reference table.

Stress Strain Calculator

Calculate engineering stress, strain, and Young modulus for materials. Free online stress strain calculator for mechanical and civil engineering.

Tangential Velocity Calculator

Calculate tangential velocity v = 2pr/T for circular motion. Free online tangential velocity calculator for physics and engineering.

Subwoofer Box Calculator

Design and compare sealed, ported, and bandpass subwoofer enclosures using Thiele-Small parameters. Calculate box volume, tuning frequency, and port length.

Subwoofer Vent Calculator

Calculate subwoofer port length and minimum vent diameter for bass reflex enclosures. Tune your subwoofer box with precise Helmholtz resonator calculations.

Pool Water Maintenance Calculator

Calculate pool turnover rate, volume, pump flow rate, and Langelier Saturation Index (LSI) for balanced pool water chemistry.

Thermal Conductivity Calculator

Calculate heat flux, thermal conductivity, temperature difference, and wall thickness using Fourier law of heat conduction. Free online thermal conductivity calculator.

Thermal Diffusivity Calculator

Calculate thermal diffusivity, thermal conductivity, density, or specific heat capacity using the thermal diffusivity formula. Free online thermal diffusivity calculator.

Thermal Expansion Calculator

Calculate linear and volumetric thermal expansion using expansion coefficients. Free online thermal expansion calculator for materials engineering.

Banana Radiation Calculator

Convert radiation exposure values into Banana Equivalent Doses (BED) and compare with common radiation sources like X-rays and flights.

Dilution Calculator

Calculate solution dilutions using the M₁V₁ = M₂V₂ equation. Find stock volume, final volume, or resulting concentration for lab dilutions.

Electric Field Calculator

Calculate electric field strength from point charges using Coulomb law with vector superposition, potential, and step-by-step solutions.

Empirical Formula Calculator

Determine empirical and molecular formulas from element mass percentages or experimental mass data with step-by-step solutions.

Entropy Calculator

Calculate Shannon entropy of probability distributions with step-by-step breakdown, perplexity, and redundancy metrics.

Falling Through Earth Calculator

Calculate travel time, max speed, and weightlessness when falling through a frictionless Earth tunnel using uniform and PREM density models.

Helium Balloon Lift Calculator

Calculate how many helium balloons you need to lift any object using Archimedes buoyancy principle. Includes fun presets, balloon types, and altitude effects.

Kinematics Calculator

Solve kinematic equations of motion online. Input any three SUVAT variables (displacement, initial velocity, final velocity, acceleration, and time) to calculate the remaining unknowns with step-by-step math explanations.

Kinetic Energy Chicken Cooker

Calculate how many slaps (or how much speed/kinetic energy) it would take to cook a chicken. An interactive physics simulation based on thermodynamics and kinetic energy conversion formulas.

Molar Mass Calculator

Calculate the molar mass (molecular weight) of any chemical formula with elemental composition breakdown.

Activation Energy Calculator

Calculate activation energy (Ea) for chemical reactions using the Arrhenius equation. Free online activation energy calculator with support for temperature, rate constant, and frequency factor inputs.

Activity Coefficient Calculator

Calculate the activity coefficient of an ion in dilute solution using the Debye-Huckel limiting law with ionic strength and charge number.

Alligation Calculator

Calculate the ratio and volumes needed to mix two solutions of different concentrations to obtain a desired intermediate concentration.

Arrhenius Equation Calculator

Calculate the rate constant of a chemical reaction using the Arrhenius equation with activation energy, temperature, and pre-exponential factor.

Atom Calculator

Calculate the number of protons, neutrons, and electrons in any atom or ion. Enter atomic number, mass number, and charge to find atomic composition.

Atom Economy Calculator

Calculate the atom economy of chemical reactions. Measure how efficiently reactants are converted to desired products in green chemistry.

Atomic Mass Calculator

Calculate the atomic mass of any atom from its number of protons and neutrons. Get results in atomic mass units (amu) and kilograms.

Average Atomic Mass Calculator

Calculate the average atomic mass of elements from isotope masses and natural abundance percentages. Free online average atomic mass calculator for chemistry.

Avogadro Number Calculator

Calculate the number of atoms or molecules in any substance using Avogadro's number. Free online Avogadro's constant calculator for chemistry.

Beer Lambert Law Calculator

Calculate absorbance, transmittance, concentration, path length, or molar absorptivity using Beer-Lambert law. Free online Beer's law calculator for spectroscopy.

Bleach Dilution Calculator

Calculate the exact amount of bleach and water needed for disinfection, pool maintenance, and water purification. Free online bleach dilution calculator.

Boiling Point Calculator

Calculate the boiling point of water and common substances at any pressure using the Clausius-Clapeyron equation. Free online boiling point calculator with support for multiple substances.

Boiling Point at Altitude Calculator

Calculate the boiling point of water at any altitude above sea level. Free online boiling point at altitude calculator using standard atmospheric pressure formulas.

Boiling Point Elevation Calculator

Calculate the boiling point elevation of solutions using molality, ebullioscopic constants, and Van't Hoff factor. Free online boiling point elevation calculator for chemistry.

Bond Order Calculator

Calculate the bond order of molecules using molecular orbital theory. Free online bond order calculator for chemistry students and professionals.

Buffer Capacity Calculator

Calculate the buffer capacity of your solution by entering the amount of acid/base added and the change in pH. Free online buffer capacity calculator for chemistry.

Buffer pH Calculator

Calculate the pH of buffer solutions using the Henderson-Hasselbalch equation. Free online buffer pH calculator for chemistry students and professionals.

Calibration Curve Calculator

Calculate unknown concentration from a calibration curve using the standard addition method. Free online calibration curve calculator for analytical chemistry.

Radiocarbon Dating Calculator

Determine the age of organic artifacts using carbon-14 dating. Enter the percentage of C-14 remaining to calculate the time elapsed since death.

Chemical Equation Balancer

Balance any chemical equation instantly with our free online balancer. Supports complex reactions with polyatomic ions, brackets, and stoichiometric coefficients.

Chemical Name Calculator

Name ionic compounds from their cation and anion. Free online chemical name finder for binary ionic compounds, polyatomic ions, and acids.

Chemical Oxygen Demand Calculator

Calculate chemical oxygen demand (COD) for water quality analysis. Enter FAS blank volume, FAS sample volume, normality, and sample volume to get COD in mg/L.

pKa Calculator

Calculate pKa from the acid dissociation constant Ka using pKa = -log10(Ka). Free online pKa calculator for chemistry.

Combustion Analysis Calculator

Find empirical and molecular formulas of organic compounds from combustion analysis data including CO2 and H2O masses.

Combustion Reaction Calculator

Balance complete combustion reactions for C, H, O organic compounds instantly. Enter carbon, hydrogen, and oxygen atom counts to get the balanced equation.

Concentration Calculator

Convert between molarity and mass percentage concentration, and calculate solute mass or grams per 100 g of water from solution data.

Crude Protein Calculator

Calculate crude protein percentage from Kjeldahl nitrogen titration data or known nitrogen content using Jones conversion factors for food and feed samples.

Cubic Cell Calculator

Calculate the lattice constant of simple cubic, BCC, and FCC unit cells from atomic radius for crystallography and materials science.

Degree of Unsaturation Calculator

Calculate the degree of unsaturation (DoU), also known as IHD or double bond equivalents, from a molecular formula with C, H, N, and halogen atoms.

Detention Time Calculator

Calculate detention time, retention time, or residence time of a tank or basin from volume and flow rate with unit conversions for water treatment and process engineering.

Diffusion Coefficient Calculator

Calculate the diffusion coefficient from temperature, viscosity, and particle shape using the Einstein-Smoluchowski relation.

Dilution Factor Calculator

Calculate dilution factor ratios (S:D and S:T) from stock, dilutant, and total volumes with real-time results.

Effective Nuclear Charge Calculator

Calculate effective nuclear charge (Zeff) for any electron using Slater rules with shielding breakdown and orbital selection.

Electrolysis Calculator

Calculate mass deposited or dissolved at electrodes using Faraday first law with electrochemical constants for common elements.

Cell EMF Calculator

Calculate galvanic cell electromotive force from cathode and anode standard electrode potentials with metal lookup table.

Electron Configuration Calculator

Find full and shorthand electron configurations, valence electrons, and atomic data for all 118 elements.

Electronegativity Calculator

Compare Pauling electronegativity values of two elements to find electronegativity difference and predict ionic, polar covalent, or covalent bonds.

Chemical Entropy Calculator

Calculate entropy change for reactions, Gibbs free energy, and ideal gas isothermal entropy from volume or pressure changes.

Enzyme Activity Calculator

Calculate enzyme mass needed for a target activity in buffer from stock activity and final volume using the enzyme activity formula.

Equilibrium Constant Calculator

Compute equilibrium constant K from reactant and product concentrations and stoichiometric coefficients for reversible reactions.

Freezing Point Depression Calculator

Calculate freezing point depression, solution freezing point, molality, or cryoscopic constant using ΔTf = i·Kf·m.

Graham's Law Calculator

Compare gas diffusion or effusion rates using Graham's law from molar masses and rate ratios.

Grams to Moles Calculator

Convert grams to moles using molar mass. Also solve for mass or molar mass from moles with preset common substances.

Heat of Combustion Calculator

Calculate heat of combustion (higher heating value) from lower heating value, water vaporization, and mole ratios for common fuels.

Hydrogen Ion Concentration Calculator

Convert between pH, pOH, and hydrogen ion concentration [H+] with real-time calculations at 25°C.

Ionic Strength Calculator

Calculate ionic strength from ion concentrations and charge numbers using I = ½Σ(cᵢzᵢ²) for up to 10 ions.

Isoelectric Point Calculator

Calculate the isoelectric point (pI) of amino acids and proteins from pKa and pKb values using the standard biochemistry formula.

Kp Calculator

Convert between Kc and Kp equilibrium constants, or calculate Kp from partial pressures for gaseous reactions.

Langmuir Isotherm Calculator

Calculate surface coverage fraction and percent using the Langmuir adsorption isotherm model with equilibrium constant and partial pressure.

Lattice Energy Calculator

Estimate lattice energy of ionic compounds using the Kapustinskii equation with ion charges, radii, and stoichiometry.

Liquid Ethylene Density Calculator

Calculate liquid ethylene (C2H4) density from mass and volume or look up saturated density by pressure and temperature.

Mass Percent Calculator

Solve for solute mass, solvent mass, solution mass, or mass percentage in chemistry mixtures.

Michaelis Menten Equation Calculator

Calculate enzyme reaction rate, Vmax, Km, or substrate concentration using the Michaelis-Menten equation.

Miller Indices Calculator

Calculate interplanar spacing d_hkl for cubic crystal systems from Miller indices and lattice constant.

Mixing Ratio Calculator

Calculate mixing ratios and percentages for up to 6 substances by mass or volume with scale multiplier.

Molality Calculator

Calculate molality from moles and solvent mass, or from solute mass and molar mass with real-time results.

Molar Mass of Gas Calculator

Find molar mass and moles of a gas using the ideal gas law from pressure, temperature, volume, and mass.

Molar Ratio Calculator

Compute molar ratios from balanced chemical equations and solve for required moles or masses.

Mole Fraction Calculator

Calculate mole fraction and mole percent from solute, solvent, or total solution moles with step-by-step results.

Nernst Equation Calculator

Calculate reduction potential using the Nernst equation from standard potential, temperature, electrons transferred, and ion activities.

Normality Calculator

Calculate normality, mass, equivalent weight, or solution volume for acids and bases using the normality formula.

Osmotic Pressure Calculator

Calculate osmotic pressure from concentration, temperature, dissociation factor, and osmotic coefficient using the Van't Hoff equation.

Net Ionic Equation Calculator

Write complete ionic and net ionic equations from molecular reactions. Identify spectator ions and balance charge automatically.

Neutralization Calculator

Calculate normality, mass, equivalent weight, or volume for acid-base neutralization reactions using the normality formula.

Partial Pressure Calculator

Calculate partial pressure using Daltons law, ideal gas law, or Henrys law with mole fraction and concentration.

Percentage Concentration to Molarity Calculator

Convert percentage concentration to molarity or molarity to percentage using density and molar mass.

Percent Composition Calculator

Calculate percent composition by mass for up to five elements from atomic counts and molar mass.

Percent Ionic Character Calculator

Calculate bond ionic character from electronegativity difference or dipole moment using Pauling's formula.

Percent Solution Calculator

Calculate mass/volume percent, weight percent, volume percent, and ppm for chemical solutions.

Phase Rule Calculator

Calculate degrees of freedom using Gibbs phase rule F = C - P + factor for chemical thermodynamics.

PPM to Molarity Calculator

Convert between ppm and molarity for aqueous solutions using molar mass. Bidirectional conversion with step-by-step calculations.

Protein Solubility Calculator

Calculate protein solubility percentage from Kjeldahl titration data including blank titer, titer, NaOH normality, and sample weight.

Q10 Calculator

Calculate the Q10 temperature coefficient from reaction rates at two temperatures, or solve for any missing variable.

Radioactive Decay Calculator

Calculate radioactive activity in Becquerels and specific activity from sample mass, molar mass, and half-life.

Raoult's Law Calculator

Calculate vapor pressure of ideal solutions using Raoult's law from solvent mole fraction or moles of solute and solvent.

Rate Constant Calculator

Compute reaction rate constant k, reaction rate, and half-life for zero, first, and second-order reactions.

Reaction Quotient Calculator

Calculate reaction quotient Q from reactant and product concentrations and compare with equilibrium constant K.

Reconstitution Calculator

Calculate reconstitution concentration, dose mass, or diluent volume when mixing powdered drugs with liquid diluent.

Resuspension Calculator

Calculate diluent volume to resuspend oligonucleotides to a desired concentration. Free online oligo resuspension calculator for molecular biology.

Saponification Value Calculator

Calculate saponification value (SV) of fats and oils from titration data. Determine soap-making potential and lye requirements.

TDS Calculator

Calculate total dissolved solids from water chemistry analysis or electrical conductivity. Free online TDS calculator for water quality.

Theoretical Yield Calculator

Calculate theoretical yield from limiting reagent mass, molecular weight, and stoichiometry. Free chemistry yield calculator with step-by-step results.

Titration Calculator

Calculate unknown acid or base molarity from titration data using the equivalence point equation nH+·Ma·Va = nOH-·Mb·Vb.

Two Photon Absorption Calculator

Calculate two-photon excitations per molecule from laser power, wavelength, FWHM, cross-section, and exposure time.

Vapor Pressure Calculator

Calculate vapor pressure at different temperatures using the Clausius-Clapeyron equation or Raoult's law for solutions.

Vapor Pressure of Water Calculator

Calculate water vapor pressure at any temperature using Antoine, Magnus, Tetens, Buck, and simplified formulas.

Water Hardness Calculator

Calculate water hardness from calcium and magnesium concentrations. Free online water hardness calculator with soft, moderate, hard, and very hard classification.

Young Laplace Equation Calculator

Calculate capillary pressure and liquid rise height using the Young-Laplace equation. Free online calculator for surface tension, contact angle, and tube radius.

PPM Calculator

Convert between percent, per mille, PPM, PPB, and PPT concentration ratios in real time.

Radiation Converter

Convert absorbed and equivalent radiation dose between Gy, rad, Sv, rem, mSv, and banana equivalent dose.