All Calculators

Work out how much mulch you need to cover a bed — in cubic yards, cubic feet, and standard 2-cubic-foot bags — from the area and the depth you want.

Work out how many litres of paint you need from your wall area, the number of coats, and the paint's coverage per litre.

Use our planet visibility calculator to find out which planets are visible tonight. Get exact altitude, direction, and moon glare data for your location.

Find the right ski length for your height, ability, and skiing style, with a suggested range to shop within.

Find the recommended surfboard volume in litres for your weight, ability, and fitness — with a suggested range to shop within.

Work out how many tiles you need to cover a floor area, including a waste allowance for cuts and breakages.

Work out how many rolls of wallpaper you need to cover a wall area, including a waste allowance for pattern matching and trimming.

Convert your exam percentage to the 15-point KMK grading scale used across all German states. Instantly see your Notenpunkte, Schulnote, and how close you are to the next grade.

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.

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

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.

Free AP Calculus AB score calculator and BC score calculator. Predict your exam score (1-5) with AP Calculus score distribution data.

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.

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

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

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 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 the total surface area, lateral surface area, and base area of a cylinder from its radius and height — total = 2πr² + 2πrh, lateral = 2πrh, base = πr².

Calculate the volume, lateral surface area, and total surface area of a cylinder from its radius and height.

Convert digital storage between bits, bytes, kilobytes, megabytes, gigabytes, terabytes and their binary counterparts — KiB, MiB, GiB, TiB.

Convert data transfer rates between bit/s, kbit/s, Mbit/s, Gbit/s, B/s, kB/s, MB/s, and more — instantly, and see why a 100 Mbit/s line downloads at only 12.5 MB/s.

Calculate density from mass and volume — density = mass ÷ volume, in kilograms per cubic metre (kg/m³).

Work out how much concentrate and water to mix for a given dilution ratio like 1:10, for any target volume.

Calculate the final price after a discount and the amount you save from an original price and a discount percentage.

Calculate the straight-line (Euclidean) distance between two points (x1, y1) and (x2, y2) — distance = √((x2−x1)² + (y2−y1)²) — plus the horizontal and vertical legs.

Calculate efficiency from useful output and total input — efficiency = (output ÷ input) × 100, as a percentage (%).

Work out what an appliance costs to run per day, month, and year from its wattage, daily run time, and your price per kilowatt-hour.

Calculate the area and circumference of an ellipse from its two semi-axes — area = πab, with Ramanujan's accurate perimeter approximation.

Convert energy between joule, kilojoule, megajoule, calorie, kilocalorie, watt-hour, kilowatt-hour, BTU, and foot-pound — instantly and with exact, joule-based conversion factors.

Calculate the area, height, and perimeter of an equilateral triangle from its side length — area = (√3/4)s², height = (√3/2)s, perimeter = 3s.

Calculate base raised to an exponent (base ^ exponent) — including negative and fractional exponents — with a worked example.

Calculate n! (n factorial) — the product of all positive integers up to n, with 0! = 1 by definition. Supports values from 0! up to 170!.

Calculate the error quotient and grade points for language exams.

Find the nth Fibonacci number F(n) with F(0) = 0 and F(1) = 1 — the sequence 0, 1, 1, 2, 3, 5, 8, 13 where each term is the sum of the two before it.

Find out exactly what you need on your final exam to hit your target course grade. Enter your current grade, desired grade, and the final's weight.

Convert force between newton, kilonewton, dyne, kilogram-force, pound-force, and more — instantly and with exact, newton-based conversion factors.

Calculate the distance an object falls and the velocity it reaches in free fall after a given time, ignoring air resistance — distance = ½ × g × t² and velocity = g × t.

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

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

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

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

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.

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