Mathematics

Calculate the straight-line (Euclidean) distance between two points (x1, y1, z1) and (x2, y2, z2) in space — distance = √((x2−x1)² + (y2−y1)² + (z2−z1)²) — plus the three axis legs.

Calculate the absolute humidity (grams of water vapour per cubic metre of air) from the air temperature (°C) and relative humidity (%) using the standard meteorological approximation.

Convert acceleration between m/s², ft/s², standard gravity (g), galileo, km/h/s, and mph/s — instantly and with exact, m/s²-based conversion factors.

Calculate your ACT composite score from the four section scores (English, Math, Reading, Science) and see the national percentile rank.

Calculate the density of dry air (kg/m³) from its absolute pressure and temperature using the ideal gas law, ρ = P / (R × T).

Calculate the atmospheric pressure at a given altitude with the barometric formula for the troposphere — enter a height in metres to get the pressure in pascals.

Convert amps and volts to watts instantly using Watt's law (P = V × I). Also computes resistance in ohms — handy for household circuits, EV charging, and electronics projects.

Calculate the angle between two 3D vectors from cosθ = (A·B) / (|A| |B|), with the result in degrees from 0 to 180.

Convert angles between degrees, radians, gradians (gon), arcminutes, arcseconds, and turns — instantly and with exact, degree-based conversion factors.

Calculate angular acceleration (α = (ω₂ − ω₁) / t) in rad/s² from an initial and final angular velocity over a time interval.

Convert an ordinary frequency in hertz into the angular frequency ω = 2πf in radians per second.

Calculate the angular momentum (L = m·v·r) of a point mass moving in a circle, in kg·m²/s, from its mass, tangential speed, and radius.

Calculate the angular size (apparent size) of an object in radians and degrees from its physical size and distance using the small-angle approximation.

Calculate angular velocity (ω = 2π·f) in rad/s from a rotational frequency, plus the tangential speed at a given radius.

Calculate the area and arc lengths of an annular sector (a slice of a ring) from its inner radius, outer radius, and central angle in degrees.

Calculate the area of an annulus (a flat ring) and its width from the outer and inner radii — area = π(R² − r²), width = R − r.

Calculate the half-wave dipole and quarter-wave antenna length in metres from a frequency in MHz and a velocity factor (λ = c / f).

Free AP Calculus AB score calculator. Predict your exam score (1-5) from multiple choice and free response performance. Cut scores are calibrated for AP Calculus AB (BC uses different thresholds).

Free AP Chemistry score calculator. Turn your multiple-choice and free-response raw scores into a predicted 1-5 AP score on the 150-point composite scale.

Free AP Psychology score calculator for the redesigned exam. Turn your multiple-choice count and your AAQ and EBQ rubric scores into a predicted 1-5 AP score.

Free AP Statistics score calculator. Turn your multiple-choice count, your five free-response scores and the investigative task into a predicted 1-5 AP score.

Free AP US Government score calculator. Turn your multiple-choice count and the four free-response rubric scores into a predicted 1-5 AP score.

Calculate the apparent brightness (radiant flux) of a star or light source in W/m² from its luminosity and distance using the inverse-square law.

Calculate the arc length of a circle (s = 2πr·θ/360) and the area of the matching circular sector from a radius and a central angle in degrees.

Convert area between metric and imperial units — square millimetres, square centimetres, square metres, hectares, square kilometres, square inches, square feet, square yards, acres, and square miles.

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

Calculate the reaction rate constant k = A · exp(−Ea / (R · T)) from the pre-exponential factor, activation energy, and absolute temperature.

Reduce any pixel width and height to its simplest whole-number aspect ratio, such as 1920 × 1080 to 16:9, with the decimal ratio shown alongside.

Calculate average acceleration from initial velocity, final velocity, and time — acceleration = (vf − vi) ÷ t, in m/s².

Calculate the ideal banking angle of a curve (θ = arctan(v²/rg)) in degrees — the angle that needs no friction to hold a vehicle on the road at a given speed and radius.

Calculate the ideal battery life of a device in hours and minutes from its battery capacity (mAh) and the current it draws (mA).

Calculate the beat frequency (f_beat = |f₁ − f₂|) in hertz from two superimposed wave frequencies.

Calculate the absorbance of light through a solution (A = ε·c·l) from the molar absorptivity, concentration, and path length.

Calculate the length of an open belt around two pulleys from the centre distance and the large and small pulley diameters.

Calculate the boiling point elevation (ΔTb = i · Kb · m) of a solution from the van 't Hoff factor, the ebullioscopic constant, and the molality.

Calculate the space diagonal, volume, and surface area of a rectangular box (cuboid) from its length, width, and height — diagonal = √(l²+w²+h²).

Calculate the final pressure of an ideal gas at constant temperature using Boyle's law (P₁V₁ = P₂V₂) from the initial pressure, initial volume, and final volume.

Calculate the buoyant force (F = ρgV) in newtons on a submerged or floating object from the fluid density and the displaced volume.

Calculate the capacitance (C = Q / V) in farads and microfarads of a capacitor from the charge it stores and the voltage across it.

Calculate the capacitive reactance (Xc = 1 / (2πfC)) in ohms of a capacitor at a given AC frequency from its capacitance and frequency.

Calculate the stored charge and energy of a capacitor from its capacitance and voltage — charge = C × V and energy = ½ × C × V².

Calculate the energy stored in a charged capacitor (E = ½CV²) in joules from its capacitance and voltage.

Calculate the maximum (Carnot) efficiency of a heat engine, η = 1 − T_cold / T_hot, from the cold and hot reservoir temperatures in kelvin.

Calculate the center of mass (balance point) of two point masses on a line from their masses and positions: x_cm = (m1·x1 + m2·x2) / (m1 + m2).

Calculate the centripetal acceleration (a = v²/r) in metres per second squared for an object moving in a circle, from its speed and the radius.

Calculate the centripetal force (F = mv²/r) in newtons that keeps an object moving in a circle, from its mass, speed, and radius.

Calculate the final volume of a gas at constant pressure using Charles's law (V₁/T₁ = V₂/T₂) from its initial volume and absolute Kelvin temperatures.

Calculate the area, circumference, and diameter of a circle from its radius — area = πr², circumference = 2πr, diameter = 2r.

Calculate the area, arc length, and chord of a circular sector from its radius and central angle — area = (θ/360)·πr², arc length = (θ/360)·2πr.

Calculate the area, arc length, chord, and sagitta of a circular segment from the radius and central angle — area = ½r²(θ − sin θ), arc = rθ, chord = 2r·sin(θ/2), sagitta = r(1 − cos(θ/2)).