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Kordu Tools

Math & Numbers

Number theory, statistics, geometry, algebra, and scientific calculators

Fraction Calculator

Add, subtract, multiply, or divide fractions with step-by-step solutions. Simplify and convert between fractions, decimals, and percentages.

Ratio Calculator

Simplify ratios, scale to a target, compare ratios, and convert to fractions or percentages. Includes aspect ratio presets.

Exponent & Power Calculator

Calculate x raised to the power of n, with support for negative and fractional exponents, and scientific notation output.

Square Root Calculator

Calculate square roots, cube roots, and nth roots with radical simplification and configurable decimal precision.

Logarithm Calculator

Calculate common log, natural log, binary log, or any custom-base logarithm with antilog support.

GCD & LCM Calculator

Find the greatest common divisor and least common multiple of two or more numbers with step-by-step prime factorization.

Prime Number Tools

Check if a number is prime, find its prime factorization, list primes in a range, or find the Nth prime number.

Factorial Calculator

Calculate n factorial, double factorial, subfactorial, trailing zeros, and digit count with large number support.

Fibonacci Generator

Generate Fibonacci sequences, check if a number is Fibonacci, and see the golden ratio convergence.

Random Number Generator

Generate random numbers, roll dice, flip coins, or pick random items from a list. Cryptographic option available.

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Number Base Converter

Convert numbers between binary, decimal, hexadecimal, octal, and any base from 2 to 36 with live updates.

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Roman Numeral Converter

Convert between numbers and Roman numerals instantly. Supports 1-3999 with validation, batch mode, and a quick-reference table.

Number to Words Converter

Convert numbers to English words, currency format, or ordinals. Supports very large numbers and multiple currencies.

Percentage Calculator

Calculate percentages instantly — find X% of Y, what percentage X is of Y, or the percentage change between two values.

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Statistics Calculator

Calculate mean, median, mode, standard deviation, variance, quartiles, and more from a data set. Includes histogram.

Probability Calculator

Calculate single event, compound, conditional, and Bayes theorem probabilities with formula display.

Permutation & Combination Calculator

Calculate permutations (nPr) and combinations (nCr) with step-by-step formula breakdown and large number support.

Triangle Calculator

Solve triangles by entering sides and angles. Supports SSS, SAS, ASA, AAS modes with area, perimeter, and SVG diagram.

Circle Calculator

Calculate radius, diameter, circumference, and area from any one value. Includes arc length and sector area calculations.

Area & Perimeter Calculator

Calculate area and perimeter for rectangles, squares, triangles, parallelograms, trapezoids, ellipses, and regular polygons.

Volume & Surface Area Calculator

Calculate volume and surface area for cubes, spheres, cylinders, cones, pyramids, and more 3D shapes.

Quadratic Equation Solver

Solve ax2 + bx + c = 0 with real or complex roots, step-by-step solution, vertex, and parabola graph.

Scientific Calculator

A full-featured scientific calculator with trigonometry, logarithms, exponents, memory, and calculation history.

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Matrix Calculator

Perform matrix operations including addition, multiplication, determinant, inverse, transpose, and row echelon form.

Grade Calculator

Calculate weighted grades, GPA, and what you need on your final exam. Supports multiple grading systems.

Tackle mathematical problems quickly with our free online calculators and number tools. Perform percentage calculations, convert between number bases, solve equations, compute statistical measures, work with fractions and matrices, and explore geometry. Whether you are a student, teacher, or professional, these tools make number crunching effortless.