All Calculators

Calculate the freezing point depression (ΔTf = i·Kf·m) of a solution from the van 't Hoff factor, the cryoscopic constant, and the molality.

Convert frequency between hertz, kilohertz, megahertz, gigahertz, terahertz, and rpm — instantly and with exact, hertz-based conversion factors.

Convert a frequency in hertz to its period (T = 1/f) in seconds and angular frequency (2πf) in radians per second.

Calculate the friction force (F = μN) in newtons from the coefficient of friction and the normal force pressing two surfaces together.

Convert fuel economy between L/100km, MPG (US), MPG (UK), and km/L — handling the inverse relationship between fuel consumption and efficiency.

Calculate g-force from an acceleration in m/s² by dividing by standard gravity (g₀ = 9.80665 m/s²) to express it as a multiple of Earth's gravity.

Find the greatest common factor (GCF) and least common multiple (LCM) of two integers using the Euclidean algorithm, with the full working shown.

Calculate the gear ratio (driven ÷ driver teeth) of a gear pair and the resulting output shaft speed in rpm from the input speed.

Calculate the geometric mean (G = √(a · b)) of two positive values and compare it with their arithmetic mean.

Find the nth term and the sum of the first n terms of any geometric sequence from its first term and common ratio.

Calculate the change in Gibbs free energy (ΔG = ΔH − T·ΔS) in joules per mole from a reaction's enthalpy change, temperature, and entropy change.

Work out how much a glass pane weighs from its length, width, thickness and material. Handy before you lift it, hang it, or ask two people to carry it.

Split a total length into a longer and shorter part in the golden ratio φ ≈ 1.618, so that the longer part divided by the shorter part equals phi.

Calculate your GPA on the 4.0 scale from your course grades and credit hours, with an optional prior GPA to work out your cumulative GPA.

Enter a grade on any of four scales and see it on all of them: US 4.0 GPA, percentage, 10-point CGPA and the German 1-6 grade.

Enter a raw score and pick a curve. You get the curved percentage, the points gained, and what all four common curves would do to the same score.

Calculate the gravitational force (F = G·m₁·m₂/r²) in newtons between two masses from their masses and the distance between their centres.

Calculate the remaining quantity of a decaying substance, N = N₀ × (½)^(t / t½), and the percentage still present from the initial amount, half-life, and elapsed time.

Calculate the harmonic mean (H = 2ab / (a + b)) of two positive values and compare it with their arithmetic mean.

Calculate the great-circle (as-the-crow-flies) distance between two points on Earth from their latitude and longitude — the haversine formula with the mean Earth radius (6371 km), in kilometres and miles.

Calculate the heat capacity C = Q / ΔT in J/K from the heat energy added and the temperature change of a whole object.

Calculate the steady-state rate of conductive heat transfer through a wall or insulation layer with Fourier's law (Q = k·A·ΔT/d), in watts.

Calculate heat energy in joules from mass, specific heat, and temperature change using Q = m × c × ΔT.

Calculate the NWS "feels-like" heat index from air temperature (°F) and relative humidity (%) using the full Rothfusz regression — and see the result in both °F and °C.

Convert a height in centimetres to feet and inches with exact international conversion factors.

Calculate the volume, curved surface, and total surface area of a hemisphere from its radius using V = 2/3 × π × r³, A = 2 × π × r², and total = 3 × π × r².

Calculate the pH of a buffer solution with the Henderson-Hasselbalch equation (pH = pKa + log₁₀([A⁻]/[HA])) from the pKa and the base and acid concentrations.

Calculate the area of a triangle from its three side lengths using Heron's formula, plus the perimeter — no height or angles needed.

Calculate the area, perimeter, apothem, and diagonals of a regular hexagon from its side length — area = (3√3/2)s², perimeter = 6s, apothem = (√3/2)s, long diagonal = 2s, short diagonal = √3·s.

Calculate the volume, cross-sectional area, and surface area of a regular hexagonal prism from its side length and length — volume = (3√3/2)·s²·L.

Weighted and unweighted high-school GPA side by side on the US 4.0 scale, so you can see exactly what honors and AP coursework adds.

Calculate spring force and elastic potential energy from a spring constant and displacement using Hooke's law — force = k × x and PE = ½ × k × x².

Calculate the distance to a receding galaxy with Hubble's law (d = v / H₀) in megaparsecs and millions of light-years from its recession velocity.

Calculate the Canadian humidex "feels-like" index from the air temperature (°C) and dew point (°C) — humidex = T + 0.5555·(e − 10), with e from the vapour-pressure formula.

Calculate the hydrostatic pressure (P = ρgh) in pascals and kilopascals from a fluid's density and depth.

Solve the ideal gas law PV = nRT for the amount of substance n = (P × V) / (R × T) in moles from the pressure, volume, and temperature of a gas.

Generate official IHK grading tables instantly. Convert maximum exam points to specific grades 1-6 using the standard 92-81-67-50-30 DIHK percentage key.

Calculate the average impact force of a collision from the work–energy principle — force = ½mv² / stopping distance — plus the kinetic energy and equivalent g-force.

Calculate the magnitude of a series RLC impedance (|Z| = √(R² + X²)) in ohms from a resistance and a net reactance.

Calculate impulse — J = F × Δt — the force applied over a time interval, which equals the change in momentum (N·s = kg·m/s).

Calculate the inductive reactance (Xl = 2π × f × L) in ohms of a coil or inductor from its inductance and the AC signal frequency in hertz.

Calculate the energy stored in an inductor's magnetic field (E = ½LI²) in joules from its inductance and the current flowing through it.

Calculate the initial compass bearing (forward azimuth) from one point on Earth to another from their latitude and longitude — the direction in degrees (0° = North, 90° = East, 180° = South, 270° = West) you would set off in.

Calculate how the intensity of a point source (light, sound, radiation) falls with distance — I₂ = I₁·(d₁/d₂)². Doubling the distance quarters the intensity.

Calculate the area, height, perimeter, base angle, and apex angle of an isosceles triangle from its base and equal-side leg — area = ½ × base × height.

Calculate the kinetic energy (KE = ½mv²) in joules and the linear momentum of a moving object from its mass and velocity.

Calculate the area of a kite from its two diagonals — area = ½ × p × q.

Generate a fair grading scale with a custom passing threshold (Knick), as used in German schools. Instantly calculate exact point boundaries for German grades 1 to 6.

Convert kVA to kW instantly — enter apparent power and power factor to get real power in kilowatts and reactive power in kVAR using the power triangle formula.

Convert kilowatts to kilovolt-amperes instantly by entering your real power and power factor — essential for sizing generators, transformers, and UPS systems correctly.