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Number System Converter
Convert any number between Binary, Octal, Decimal and Hexadecimal — with full step-by-step working for every conversion.
BIN Base 2 0–1
OCT Base 8 0–7
DEC Base 10 0–9
HEX Base 16 0–9, A–F
Quick examples:
📊 Quick Reference Table (0–15)
| Decimal | Binary | Octal | Hexadecimal |
|---|---|---|---|
| 0 | 0000 | 0 | 0 |
| 1 | 0001 | 1 | 1 |
| 2 | 0010 | 2 | 2 |
| 3 | 0011 | 3 | 3 |
| 4 | 0100 | 4 | 4 |
| 5 | 0101 | 5 | 5 |
| 6 | 0110 | 6 | 6 |
| 7 | 0111 | 7 | 7 |
| 8 | 1000 | 10 | 8 |
| 9 | 1001 | 11 | 9 |
| 10 | 1010 | 12 | A |
| 11 | 1011 | 13 | B |
| 12 | 1100 | 14 | C |
| 13 | 1101 | 15 | D |
| 14 | 1110 | 16 | E |
| 15 | 1111 | 17 | F |
🔵 Binary (Base 2)
- Digits: 0, 1 only
- Used in: all digital computers and electronics
- Each digit = 1 bit; 8 bits = 1 byte
- Prefix: 0b (e.g. 0b1010)
- To decimal: multiply each bit by 2^position
🟣 Octal (Base 8)
- Digits: 0 to 7
- Used in: Unix file permissions (e.g. chmod 755)
- 3 binary digits = 1 octal digit
- Prefix: 0o (e.g. 0o17)
- Easier to read than binary for large numbers
🟢 Decimal (Base 10)
- Digits: 0 to 9 — our everyday number system
- Positional: each place is a power of 10
- Hundreds = 10², Tens = 10¹, Units = 10⁰
- Standard for human use everywhere
- Converting to other bases: repeated division
🟡 Hexadecimal (Base 16)
- Digits: 0–9 then A=10, B=11, C=12, D=13, E=14, F=15
- Used in: memory addresses, HTML colours (#FF5733)
- 4 binary digits = 1 hex digit
- Prefix: 0x (e.g. 0xFF)
- Very compact representation of binary data