Convert numbers between binary, octal, decimal and hex.
A number base converter lets you instantly translate any number between the four most common numeral systems: binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Just type into any field and the other three update in real time — no button clicks needed. Whether you are doing low-level programming, working with memory addresses, or learning how computers represent numbers, this free number base converter tool gets the job done in seconds.
Type your decimal number into the Decimal (base 10) field. The Binary field will update instantly with the base-2 equivalent. For example, entering 255 gives you 11111111 in binary.
Hexadecimal (base 16) needs 16 distinct digit symbols but the regular decimal system only has 10 (0–9). The letters A through F fill in for the values 10 through 15, so a single hex digit can represent any value from 0 to 15.
Binary accepts only 0 and 1. Octal accepts digits 0–7. Decimal accepts digits 0–9. Hexadecimal accepts digits 0–9 and the letters A–F (uppercase or lowercase). The converter highlights invalid characters so you can spot mistakes quickly.
This converter works with non-negative integers. Negative numbers and decimal fractions (like 3.14) require a different encoding scheme (such as two's complement or IEEE 754 float), which is beyond the scope of a simple base conversion.