New Calculators

Calculate power from work and time — power = work ÷ time, in watts (W), with the equivalent in horsepower (hp).

Convert pressure between pascal, bar, atmosphere, psi, mmHg, and more — instantly and with exact, pascal-based conversion factors.

Calculate pressure from force and area — pressure = force ÷ area, in pascals (Pa).

Calculate the volume, base area, and slant height of a square pyramid from its base edge and height — volume = (1/3)a²h, base area = a², slant height = √(h²+(a/2)²).

Find the hypotenuse, area, and perimeter of a right triangle from its two legs using the Pythagorean theorem: c = √(a² + b²).

Solve any quadratic equation ax² + bx + c = 0 for its real roots and see the discriminant that tells you how many real solutions exist.

Calculate the time constant of an RC circuit — τ = R × C — the time it takes to charge to ~63 % or discharge to ~37 % of the final voltage.

Calculate the area, perimeter, and diagonal of a rectangle from its length and width — area = L×W, perimeter = 2(L+W), diagonal = √(L²+W²).

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

Calculate the area, perimeter, and apothem of a regular polygon from its number of sides and side length — area = ½ × perimeter × apothem, apothem = s/(2·tan(π/n)).

Calculate the combined resistance of two resistors in parallel using the product-over-sum rule — Rp = (R1 × R2) ÷ (R1 + R2).

Calculate the total resistance of two resistors in series — they simply add: R = R1 + R2.

Calculate the resonant frequency of an LC circuit from its inductance and capacitance — f = 1 ÷ (2π√(L × C)).

Calculate the area, side length, and perimeter of a rhombus from its two diagonals — area = (d1 × d2) ÷ 2.

Convert a ring's inner diameter in millimetres to US and EU/ISO ring sizes, with the inner circumference shown alongside.

Calculate your total SAT score from the Math and Reading & Writing (EBRW) section scores and see the national percentile rank.

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 combined capacitance of two capacitors in series using the product-over-sum rule — C = (C1 × C2) ÷ (C1 + C2).

Calculate the slope (gradient) and y-intercept of the line through two points — slope = (y2 − y1) ÷ (x2 − x1) and y = mx + b.

See what smoking really costs per day, month, year, and decade from how many cigarettes you smoke a day, the pack size, and the price per pack.

Calculate average speed in km/h and pace in minutes per kilometre from a distance in kilometres and a time in hours.

Calculate the speed of sound in dry air from the air temperature — v = 331.3 + 0.606 × T (T in °C), about 343 m/s at 20 °C.

Calculate the surface area of a sphere from its radius using A = 4 × π × r², plus the volume, in any unit you choose.

Calculate the volume and surface area of a sphere from its radius using V = 4/3 × π × r³ and A = 4 × π × r².

Calculate the volume, curved surface area, and base radius of a spherical cap from the sphere radius and cap height — volume = (πh²/3)(3R−h), curved surface = 2πRh, base radius = √(h(2R−h)).

Calculate the elastic potential energy (PE = ½kx²) in joules stored in a stretched or compressed spring from its spring constant and displacement.

Calculate the total square footage of a rectangular area from its length and width, with the result shown in square feet and square metres.

Convert a step count into distance in kilometres and miles using your average stride length — see how far 10,000 steps really is.

Convert torque between newton-metre, pound-foot, pound-inch, kilogram-force metre, and more — instantly and with exact, newton-metre-based conversion factors.

Calculate the volume and surface area of a torus (a donut) from its major radius R and minor radius r — volume = 2π²Rr², surface area = 4π²Rr.

Calculate the secondary voltage of an ideal transformer from its turns ratio — Vs = Vp × (Ns ÷ Np), in volts (V).

Calculate the area of a trapezoid (UK: trapezium) from its two parallel sides and the perpendicular height — area = ((a + b) / 2) × h.

Calculate the area of any triangle from its base and perpendicular height using the formula area = ½ × base × height.

Calculate the output voltage of a two-resistor voltage divider — Vout = Vin × R₂ ÷ (R₁ + R₂), in volts (V).

Calculate the wavelength and period of an electromagnetic wave from its frequency — wavelength = c ÷ f and period = 1 ÷ f.

Estimate how many pages your word count fills for common font sizes and line spacings, with single- and double-spaced results shown clearly.

Calculate the mechanical work done by a force over a distance — work = force × distance × cos(θ), measured in joules.

Calculate a z-score from a raw value, the mean, and the standard deviation — z = (x − μ) ÷ σ.

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.

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 a bond's current yield from its face value, coupon rate, and market price, with the annual coupon income and any premium or discount to par.

Price a fixed-coupon bond as the present value of its coupons plus its face value, discounted at the yield to maturity, with the premium or discount to par.

Find a bond's yield to maturity — the total annual return if held to maturity — from its price, coupon, face value, and term, with the current yield alongside.

Find the compound annual growth rate that takes a beginning value to an ending value over a number of years, with the total growth and the growth multiple.

See how a single deposit grows with compound interest at any frequency from annual to daily and continuous, with the interest earned and the effective annual rate (APY).

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

Convert hours and minutes into decimal hours for timesheets and payroll, with the total minute count shown alongside.

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

Work out the floor area of your room and how many boxes of laminate, vinyl, or hardwood flooring you need, including a waste allowance for cuts.

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