Number Theory

Base Calculator

Add, subtract, multiply, divide, or take remainders with a base calculator that accepts bases 2 to 36, mixed source bases, exact integer arithmetic.

Base Converter

Convert between bases 2 and 36 with binary, decimal, hex, octal, radix, fractional, grouped-input, and exact working-table support.

Big Number Calculator

Perform arbitrary-precision arithmetic on huge integers, decimals, and scientific-notation values, with exactness labels, grouped output.

Binary Calculator

Add, subtract, multiply, or divide base-2 integers with this binary calculator, with exact binary, decimal, octal, hex, and quotient/remainder checks.

Bitwise Calculator

Perform bitwise AND, OR, XOR, NOT, and logical shifts on exact integers with binary, decimal, hexadecimal, signed interpretation, and set-bit outputs.

Factor Calculator

Find all factors of any positive integer, displayed as individual factors and factor pairs, with a prime-or-composite check.

Fibonacci Calculator

Find the nth Fibonacci number, generate a Fibonacci sequence range, total the selected terms, and check whether a value is in the sequence.

Greatest Common Factor Calculator

Find the greatest common factor of two or more numbers using prime factorisation, with step-by-step working and factor lists.

Hex Calculator

Perform hexadecimal arithmetic — addition, subtraction, multiplication, and division — on hex values and see results in hex, decimal, binary, and octal.

Modular Arithmetic Calculator

Use the modular arithmetic calculator to reduce integers mod n, solve modular addition or multiplication, run modular exponentiation.

Number Sequence Calculator

Identify arithmetic, geometric, and other common number sequences, then find missing terms and the general formula.

Prime Factorization Calculator

Break any positive integer into prime powers with repeated-division steps, factor-tree support, and exponent notation you can reuse for GCF, LCM.

Roman Numeral Converter

Convert numbers to Roman numerals or Roman numerals to numbers with strict validation, running-total breakdowns, nearby-value checks.

Rounding Calculator

Round any number to a chosen number of decimal places, significant figures, or to the nearest whole, ten, hundred, or thousand.

Scientific Notation Calculator

Convert numbers to and from scientific notation and perform arithmetic operations on numbers in scientific form.

Significant Figures Calculator

Count significant figures in any number and round a value to a specified number of significant figures, with ambiguity notes for whole-number trailing zeros.