Number Base Converter
Convert numbers between decimal, binary, octal, and hexadecimal. Supports large numbers with grouped digit display.
Decimal (Base 10)255
Binary (Base 2)0b1111 1111
Octal (Base 8)0o377
Hexadecimal (Base 16)0xFF
Additional Info
Bits needed: 8
Bytes needed: 1
Is power of 2: No
Is even: No
Frequently Asked Questions
What are number bases?
A number base (or radix) determines how many digits are used to represent numbers. Decimal uses 10 digits (0-9), binary uses 2 (0-1), octal uses 8 (0-7), and hexadecimal uses 16 (0-9, A-F).
Why is hexadecimal used in programming?
Hexadecimal is compact — each hex digit represents exactly 4 binary digits (bits). This makes it ideal for representing memory addresses, colors (e.g., #FF0000), and byte values.
How do I read binary numbers?
Each binary digit (bit) represents a power of 2, from right to left. For example, 1010 in binary = 1×8 + 0×4 + 1×2 + 0×1 = 10 in decimal.