Supports non-negative integers. Edit any field to convert all bases.
A number base (or radix) defines how many unique digits are used. Binary uses 2 (0,1), octal uses 8 (0-7), decimal uses 10 (0-9), and hexadecimal uses 16 (0-9, A-F).
Hexadecimal is widely used in computing: memory addresses, color codes (#FF5733), byte values, and debugging output. Each hex digit represents exactly 4 binary bits.
Binary is the fundamental language of computers. All data is ultimately stored and processed as 0s and 1s. Understanding binary is essential for bit manipulation and low-level programming.
Multiply each digit by 16 raised to its position power and sum the results. For example, 0xFF = (15×16¹) + (15×16⁰) = 240 + 15 = 255.
One hexadecimal digit represents exactly 4 bits (a nibble). Two hex digits form one byte (8 bits). This is why hex is so popular for representing binary data — 0xFF is much more readable than 11111111.
Hex maps cleanly to binary: 1 hex digit = 4 bits, 2 hex digits = 1 byte. This makes bit-level operations, memory addresses, and byte values much easier to read and write than their decimal equivalents. For example, color #FF5733 directly shows 3 bytes of RGB values.
Two's complement is how computers represent negative integers in binary. To negate a number: flip all bits and add 1. For example, in 8-bit: +5 = 00000101; -5 = 11111010 + 1 = 11111011. This is why signed integers have an asymmetric range (e.g., -128 to +127 for 8-bit).
Number base conversion is a fundamental skill in programming and computer science. Binary, octal, decimal, and hexadecimal are the four most common bases — each serving a different role in code, hardware, and networking.
Enter a number in any field
Type a number in the binary, octal, decimal, or hexadecimal field. All other fields update instantly with the equivalent value in their respective base.
Use the correct prefix format
Hexadecimal values can be entered with or without the 0x prefix (both 0xFF and FF are accepted). Binary values are entered as 0s and 1s without the 0b prefix.
Verify conversions
The tool shows all four representations simultaneously — use this to double-check manual conversions or understand how a value looks in different contexts.
Handle large numbers
The tool handles arbitrarily large integers. Enter memory addresses, color codes, or permission masks without worrying about overflow.
Decode color values
CSS color #FF5733 is three hex bytes: FF (255 red), 57 (87 green), 33 (51 blue). Convert each byte to decimal to get the RGB values for use in non-CSS contexts.
Read Unix file permissions
The chmod command uses octal values (e.g. 755). Converting 7 to binary gives 111 — meaning read, write, and execute. This tool makes it visual.
Understand memory addresses
Debuggers and crash reports show memory addresses in hexadecimal. Convert them to decimal or binary to understand their magnitude or to compare with documentation.
Different number bases are fundamental to low-level programming, networking, and computer science. Decimal (base 10) is what humans use daily; binary (base 2) is what processors actually operate on; octal (base 8) appears in Unix file permissions (chmod 755); hexadecimal (base 16) is used everywhere from memory addresses and color codes to byte-level protocol fields and cryptographic output.
This converter lets you enter a number in any of the four standard bases and instantly see its representation in all others. It is particularly useful when working with bitwise operations (where binary makes the logic visible), reading memory dump output (hex), setting Linux file permissions (octal), or verifying that a hex color code corresponds to the right decimal RGB value.