Free Online Calculators
11 free math calculators for percentages, statistics, fractions, unit conversion, scientific functions, roots, exponents, ratios, and probability. Instant results as you type.
From quick percentage calculations to advanced scientific functions, having reliable math tools at your fingertips saves time and eliminates errors. ThisCalc provides 11 free math calculators that cover everyday arithmetic, statistics, algebra, unit conversion, and probability. Every tool delivers instant results as you type, with step-by-step explanations where applicable so you can understand the process as well as the answer.
The percentage calculator is one of the most-used tools on ThisCalc, handling three common scenarios: finding what X% of a number is, determining what percentage one number is of another, and calculating the percentage change between two values. Whether you are figuring out a sale discount, computing a grade, or analyzing growth rates, it gives you the answer instantly. The fraction calculator handles addition, subtraction, multiplication, and division of fractions with mixed numbers, showing each step of the solution including finding common denominators, cross-multiplying, and simplifying to the lowest terms.
When you need to analyze a set of numbers, the average calculator computes six types of averages from a single list: arithmetic mean, median, mode, geometric mean, harmonic mean, and range. For deeper statistical analysis, the standard deviation calculator provides both population and sample standard deviation, variance, standard error of the mean, coefficient of variation, and a complete five-number summary. These are essential for students, researchers, quality control professionals, and anyone working with data.
The scientific calculator is a full-featured tool with trigonometric functions (sin, cos, tan and their inverses), logarithms (log, ln), exponents, factorials, combinations, permutations, mathematical constants, and a SHIFT key for extended functions. It supports degrees, radians, and gradians mode, and includes five visual themes inspired by classic calculators (TI-84, Casio, HP 48, TI-30X). For focused work, the square root calculator handles square roots, cube roots, Nth roots, radical simplification, perfect square checking, and prime factorization, while the exponent calculator raises any base to any power with a table of common powers and inverse logarithm calculations.
The unit converter handles bidirectional conversion across length, weight, temperature, volume, area, speed, and time — covering both metric and imperial systems. The ratio calculator simplifies ratios, solves missing proportions, scales values up or down, and calculates aspect ratios for screens and images. For probability and combinatorics, the probability calculator computes event probability, combinations (nCr), permutations (nPr), and conditional probability with Bayes' theorem. The random number generator produces cryptographically random integers or decimals with options for multiple values, duplicate prevention, and sorted output — useful for lotteries, sampling, and simulations.
Every math calculator on ThisCalc runs entirely in your browser using JavaScript. There is no server processing, no data collection, and no account required. Calculations are based on standard mathematical formulas implemented with full floating-point precision. For educational use, many calculators include detailed explanations of the formulas and methods used.
To find X% of a number, multiply the number by X and divide by 100. For example, 15% of 200 is (200 x 15) / 100 = 30. Our percentage calculator handles three common scenarios: what is X% of Y, X is what percent of Y, and the percentage change between two numbers. All calculations update instantly as you type.
Mean is the arithmetic average (sum of all values divided by count). Median is the middle value when data is sorted in order. Mode is the most frequently occurring value. For symmetric distributions these three are similar, but for skewed data they can differ significantly. Our average calculator computes all three plus geometric mean, harmonic mean, range, and weighted average from any list of numbers.
To simplify a fraction, find the greatest common divisor (GCD) of the numerator and denominator and divide both by it. For example, 12/18: the GCD of 12 and 18 is 6, so 12/18 simplifies to 2/3. Our fraction calculator handles addition, subtraction, multiplication, and division of fractions with step-by-step solutions showing the work.
Standard deviation measures how spread out values are from the mean. A low standard deviation means values cluster tightly around the average, while a high standard deviation means they are spread across a wider range. Use population standard deviation when you have data for the entire group, and sample standard deviation when working with a subset. It is essential in statistics, quality control, finance (volatility), and scientific research.
Yes. The scientific calculator supports all six trigonometric functions (sin, cos, tan, csc, sec, cot), their inverse functions (arcsin, arccos, arctan), and operates in degrees, radians, or gradians mode. It also includes logarithms (log, ln), exponents, factorials, combinations (nCr), permutations (nPr), mathematical constants (pi, e), and a calculation history.