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An Integer Base Converter transforms numbers between binary (base-2), octal (base-8), decimal (base-10), hexadecimal (base-16), and any custom base up to base-36. Number base conversion is fundamental to computer science: binary is how computers process data, hexadecimal is how humans compactly represent bytes (two hex digits = one byte), and octal is used in Unix file permissions. This converter handles large integers and explains each conversion step.
Enter a number, select the source base, and choose the target base. The converter first translates the input to decimal (value = Σ digit × base^position), then from decimal to the target base (repeated division: remainder = digit, quotient continues). Custom bases beyond 16 use letters (G-Z) after F. Step-by-step breakdown is shown so you can learn the conversion method. Common presets for binary↔hex↔decimal speed up frequent conversions.
From any base to decimal: Value = Σ(digit_i × base^i)\nExample: 2A (hex) = 2×16¹ + 10×16⁰ = 42\n\nFrom decimal to base B: repeated division by B, reading remainders bottom-up\n\nCommon conversions: Binary↔Hex (group 4 bits), Binary↔Octal (group 3 bits)\nProgrammer interest: hex FF = 255 dec = 11111111 binary (1 byte max)
Hexadecimal maps directly to binary: 1 hex digit = 4 bits = 1 nybble. Two hex digits = 8 bits = 1 byte. This makes reading memory addresses, color codes, and binary data much simpler than decimal would.
Base-36 (0-9 + A-Z). Beyond base-36, you'd need more symbols than the Latin alphabet provides. For arbitrary precision with very large numbers, use our Big Number mode.
Free online Integer Base Converter — no signup, 100% client-side processing. All data stays in your browser.