Binary Converter Online Free — Binary Hex Decimal Octal
Convert between binary, hexadecimal, decimal, and octal instantly. Toggle to Text mode to encode/decode ASCII. Click individual bits to toggle them. Includes bitwise operations and common values reference.
Number Bases Quick Reference
Binary (base 2)
- Digits
- 0, 1
- Prefix
- 0b
- Example
- 0b1010 = 10
- Used for
- CPU registers, flags, bitwise ops
Octal (base 8)
- Digits
- 0–7
- Prefix
- 0o
- Example
- 0o17 = 15
- Used for
- Unix file permissions (chmod 755)
Decimal (base 10)
- Digits
- 0–9
- Prefix
- —
- Example
- 255
- Used for
- Human-readable numbers
Hexadecimal (base 16)
- Digits
- 0–9, A–F
- Prefix
- 0x
- Example
- 0xFF = 255
- Used for
- Colors, memory addresses, bytes
Frequently Asked Questions
How do I convert decimal to binary?
Select "Decimal (base 10)" as your input base, type your number (e.g. 255), and the binary equivalent appears instantly. For 255: it converts to 11111111 in binary (eight 1-bits = 2^8 - 1).
What is hexadecimal and why do programmers use it?
Hexadecimal (base 16) uses digits 0-9 and letters A-F. Each hex digit represents exactly 4 bits (one nibble), making it compact and readable for binary data. 0xFF = 11111111 in binary = 255 in decimal. CSS colors, memory addresses, and byte values are commonly written in hex.
How do I convert text to binary?
Switch to "Text ↔ Binary" mode and type your text. Each character is converted to its 8-bit ASCII code. For example, "A" (decimal 65) becomes 01000001 in binary. Spaces separate each character's binary representation.
What is the interactive bit editor?
Below the conversions, the bit editor shows your number as individual bit blocks. Click any bit to toggle it between 0 and 1. The decimal, hex, and binary values update instantly. This is useful for understanding how individual bits affect the overall value.
What bitwise operations are supported?
AND, OR, XOR, NOT, left shift (<<), and right shift (>>). Enter two operands (A and B), select the operation, and see the result in decimal, binary, and hex. NOT operates on operand A only, inverting all bits. Shift operations move bits left or right by B positions.
What does 0xFF mean?
0xFF is hexadecimal notation for the value 255. The 0x prefix indicates hexadecimal. FF = 15×16 + 15 = 255 in decimal, and 11111111 in binary (all eight bits set to 1). It represents the maximum value of an 8-bit unsigned integer (one byte).