Percentage Calculator
Solve every common percentage question — "what is X% of Y", "X is what percent of Y", and percentage change.
Solve every common percentage question — "what is X% of Y", "X is what percent of Y", and percentage change.
Compute the cosine similarity between two vectors when only the dot product and the two L2-norms are pre-computed: cos θ...
Solve a 2×2 system of linear equations { a₁x + b₁y = c₁ ; a₂x + b₂y = c₂ } using Cramer's rule, with a determinant check...
Computes an even perfect number using Euler's theorem: N = 2^(p−1) × M_p where M_p = 2^p − 1 is the Mersenne number. Kno...
Compute the hypergeometric PMF P(X = k) for sampling n items without replacement from a population of N containing K suc...
Convert any decimal — terminating or repeating — into its simplest fraction form with a short explanation.
Solves a quadratic equation ax² + bx + c = 0, reporting the discriminant Δ = b² − 4ac and both roots (real or complex ma...
Compute the percent difference between two values — the absolute difference divided by their average, expressed as a per...
Compute the electrostatic force between two point charges using Coulomb's law.
Volume, lateral surface area, and total surface area of a right circular cylinder from radius and height.
Convert a raw value into a z-score using the mean and standard deviation of its distribution, and look up the correspond...
Calculates the standard score z from a raw value, mean, and standard deviation, then estimates the cumulative normal per...
Standard deviation is "average distance from the average". That one sentence covers 90% of everything you ever need to remember about it.
Every "X% of Y" problem, every "what percent of", every percent-change question — written out the way you'd actually say them.
These calculators were technically reviewed by Daniel Oh for accuracy.
Calculate an age-based pediatric dose from a known adult dose using Young’s Rule. A quick educational tool for students...