Convert numbers between binary, octal, decimal, and hexadecimal instantly. Supports arbitrarily large numbers with BigInt precision.
Valid digits: 0-9
Enter a number above
Enter a number above
Enter a number above
Enter a number above
A number base converter is a tool that translates numbers between different numeral systems — binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). These number systems are fundamental in computing and programming. Binary is the language computers use internally, representing data as sequences of 0s and 1s. Octal was historically used in Unix file permissions and some older systems. Decimal is the standard human-readable number system. Hexadecimal is widely used in programming for memory addresses, color codes (#FF5733), MAC addresses, and any context where compact binary representation matters. This tool converts between all four bases simultaneously — enter a number in any base and instantly see its representation in the other three. It supports arbitrarily large numbers using JavaScript BigInt, meaning you can convert values well beyond the 53-bit integer limit (9,007,199,254,740,991) that standard number types impose. The bit visualization feature displays binary output in grouped nibbles (4-bit groups) with bit position labels, making it easy to inspect individual bits for debugging, bitwise operations, or learning digital logic. Everything runs in your browser with zero server calls.
Click one of the four base buttons — Binary (2), Octal (8), Decimal (10), or Hexadecimal (16) — to tell the tool what format your number is in. The input field will only accept valid digits for the selected base.
Type or paste your number into the input field. The tool validates each character in real time and shows an error if you enter an invalid digit for the selected base. Conversions to all four bases appear instantly below as you type.
Click the Copy button next to any conversion result to copy it to your clipboard. For binary output, scroll down to the bit visualization to see individual bits grouped into nibbles with position labels — useful for understanding bitwise operations and data structures.
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