All Calculators

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, 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)).

Calculate the convective cloud base (lifted condensation level) in metres and feet from the surface temperature (°C) and dew point (°C) using Espy's 125 m/°C equation.

Calculate the coefficient of restitution (e = √(bounce height ÷ drop height)) from a simple ball-bounce test, on a 0 (perfectly inelastic) to 1 (perfectly elastic) scale.

Calculate the inductance of a long single-layer air-core solenoid from its number of turns, coil radius, and coil length — L = µ₀ × N² × A / l.

Find how many steps the Collatz sequence takes from any positive integer to 1 — halving even numbers and applying 3n + 1 to odd ones — plus the highest value reached along the way.

Solve the combined gas law (P₁V₁/T₁ = P₂V₂/T₂) for the final volume of a gas from its initial pressure, volume, and temperature and the new pressure and temperature.

Calculate the modulus |z| = √(a² + b²) and the argument φ = atan2(b, a) in degrees of a complex number z = a + bi from its real and imaginary parts.

Calculate the slant height, lateral surface area, and total surface area of a conical frustum from its bottom radius, top radius, and height — slant = √((R−r)²+h²), lateral = π(R+r)l, total = lateral + πR² + πr².

Calculate the volume of a conical frustum (a cone with the top sliced off) from its bottom radius, top radius, and height.

Calculate the total and lateral surface area of a cone from its base radius and slant height — total = πr(r + l), lateral = πrl.

Calculate the volume, slant height, and lateral surface area of a cone from its radius and height — volume = (1/3)πr²h, slant height = √(r²+h²), lateral surface = πrl.

Calculate the downstream velocity of an incompressible fluid with the continuity equation (A₁v₁ = A₂v₂) from the upstream area, velocity, and downstream area.

Calculate the area of a triangle from the (x, y) coordinates of its three vertices using the shoelace formula — works for any vertex order.

Calculate the electrostatic force (F = kₑ·|q₁·q₂|/r²) in newtons between two point charges from their charges and separation distance.

Calculate the magnitude of the cross product |A × B| of two 3D vectors from their x, y, and z components.

Calculate the volume, surface area, face diagonal, and space diagonal of a cube from its side length — volume = s³, surface area = 6s², face diagonal = s√2, space diagonal = s√3.

Calculate the surface area, volume, and space diagonal of a cuboid (rectangular box) from its length, width, and height — surface area = 2(lw+lh+wh), volume = lwh, diagonal = √(l²+w²+h²).

Calculate how a total current splits between two parallel resistors — I1 = I × R2 / (R1 + R2), I2 = I × R1 / (R1 + R2).