Number Base Converter
Convert between binary, octal, decimal, hex, and any base 2–36.
Common Values
| Decimal | Binary | Octal | Hex |
|---|---|---|---|
| 0 | 0000 | 0 | 0 |
| 1 | 0001 | 1 | 1 |
| 8 | 1000 | 10 | 8 |
| 10 | 1010 | 12 | A |
| 15 | 1111 | 17 | F |
| 16 | 10000 | 20 | 10 |
| 255 | 11111111 | 377 | FF |
| 256 | 100000000 | 400 | 100 |
Frequently Asked Questions
Why do computers use binary?▼
Computers use binary (base 2) because electronic circuits have two stable states: on (1) and off (0). This maps directly to transistors. Binary is also noise-resistant — unlike analog systems, small signal variations don't change the meaning of a 0 or 1.
What is hexadecimal used for?▼
Hexadecimal (base 16) is used as a compact representation of binary. Since 16 = 2⁴, each hex digit represents exactly 4 bits. One byte (8 bits) is two hex digits. Hex is used for memory addresses, color codes (#FF5733), and data dumps.
How do you convert binary to decimal?▼
Multiply each bit by its positional power of 2, then sum them. For example: 1011 = 1×8 + 0×4 + 1×2 + 1×1 = 8 + 0 + 2 + 1 = 11.
What is base 36?▼
Base 36 uses digits 0–9 and letters A–Z (case-insensitive) — 36 total symbols. It is the most compact base that uses only alphanumeric characters. It's used for URL shorteners, unique ID generation, and compact numeric encoding.