Arithmetic & Numbers calculators
Work with whole numbers, powers and roots. Find square and cube roots in exact surd form, raise numbers to any power, calculate logarithms, test whether a number is prime, and find factors, the greatest common factor and the least common multiple. Each calculator shows the method, such as prime factorisation or Euclid’s algorithm, and checks the answer a second way.
Square Root Calculator
Find the square root of any number, simplified exactly (like √50 = 5√2) with the decimal value.
Cube Root Calculator
Find the cube root of any number, including negatives, simplified exactly (like ∛54 = 3∛2) with a decimal value and prime factor steps.
Exponents & Powers Calculator
Raise any number to a power, including negative and fractional exponents.
Logarithm Calculator
Calculate logarithms in any base, including log base 10, log base 2 and the natural log ln.
Prime Number Calculator
Check whether a number is prime, see its prime factorisation and find the next prime.
Factor Calculator
List all the factors and factor pairs of a number, with its prime factorisation, number of factors and sum of factors.
LCM Calculator
Find the least common multiple (LCM) of two or more numbers using prime factorisation and the GCF method.
GCF (HCF) Calculator
Find the greatest common factor (GCF), also called the HCF or GCD, of two or more numbers using Euclid's algorithm and prime factors.
Scientific Notation Calculator
Convert numbers to and from scientific notation (standard form), engineering notation and E notation, exactly, with the steps shown.
Rounding Calculator
Round any number to decimal places, significant figures or the nearest 10, 100 or 1000, exactly, with the deciding digit explained.
Significant Figures Counter
Count the significant figures in any number as written, with each rule explained: leading zeros, captive zeros and trailing zeros.
Roman Numeral Converter
Convert numbers from 1 to 3999 to Roman numerals and Roman numerals back to numbers, with the place-value breakdown shown.
Binary, Hex & Number Base Converter
Convert numbers between binary, decimal, hexadecimal, octal and other bases from 2 to 36, with the place-value and repeated-division steps.
Factorial Calculator
Calculate n! exactly, even for big numbers like 100!, with the number of digits and trailing zeros explained.
Remainder & Modulo Calculator
Find the quotient and remainder of any division, a mod b (including negatives), and which numbers from 2 to 12 divide it exactly.
Long Division Calculator
Do long division step by step: divide, multiply, subtract and bring down, with the quotient, remainder, decimal and mixed number.