Binary Calculator
Last updated: November 5, 2026
Convert a whole decimal number to binary, hexadecimal and octal notation.
Binary value
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- Hexadecimal: —
- Octal: —
- Bit length: —
On this page
Quick summary: Convert a whole decimal number to binary, hexadecimal and octal notation.
Read the complete guide
Updated reference sections in this guide are in English.
What this calculator estimates
Convert a whole decimal number to binary, hexadecimal and octal notation.
How to use it
Enter Decimal whole number. Select Calculate to update the results.
How the calculation works
Integer values are repeatedly divided by the target base; the remainders form the converted digits.
Worked example: starting scenario
| Decimal whole number | 255 |
|---|
| Binary value | 11111111 |
|---|---|
| Hexadecimal | FF |
| Octal | 377 |
| Bit length | 8 |
Important limitations
This converter accepts whole decimal integers only, not decimal fractions.
Sign and representation
A decimal integer of 10 is 1010 in binary, A in hexadecimal and 12 in octal. Negative numbers are displayed with a minus sign followed by the magnitude: −10 becomes −1010. This is not a fixed-width two’s-complement encoding, and the bit count describes the magnitude rather than a machine word including a sign bit. Enter decimal digits only; binary prefixes, fractions and scientific notation are not accepted.