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Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any custom base from 2 to 36.

Binary

Base 2 · 0b

Octal

Base 8 · 0o

Decimal

Base 10

Hexadecimal

Base 16 · 0x

Custom Base Converter

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Powers of 2 Reference

20 1
21 2
22 4
23 8
24 16
25 32
26 64
27 128
28 256
29 512
210 1,024
211 2,048
212 4,096
213 8,192
214 16,384
215 32,768
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How to Use Number Base Converter

To convert a number between bases, enter your value in the source base field — binary (base 2), octal (base 8), decimal (base 10), or hexadecimal (base 16). The tool instantly converts the value to all other bases and displays all four representations simultaneously.

A powers-of-two reference table at the bottom shows values from 2⁰ to 2¹⁵, useful as a quick reference for bit manipulation and binary arithmetic. This tool is ideal for computer science students, programmers working with low-level code, and anyone debugging binary or hexadecimal data.

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Frequently Asked Questions

What is the difference between binary, octal, decimal, and hexadecimal? expand_more

Binary (base 2) uses only 0 and 1. Octal (base 8) uses digits 0–7. Decimal (base 10) is the standard number system using digits 0–9. Hexadecimal (base 16) uses digits 0–9 and letters A–F.

What is 255 in hexadecimal? expand_more

255 in decimal is FF in hexadecimal. This is because 255 = (15 × 16) + 15, and 15 is represented as F in hexadecimal notation.

Why is hexadecimal commonly used in computing? expand_more

Hexadecimal provides a compact representation of binary data. Each hex digit represents exactly 4 bits, so one byte (8 bits) can be written as exactly two hex digits, making memory addresses and colour codes much shorter than their binary equivalents.

What is 10 in binary? expand_more

The decimal number 10 is 1010 in binary. Binary represents numbers using powers of 2: 1×8 + 0×4 + 1×2 + 0×1 = 10.

Can I convert negative numbers or fractional numbers? expand_more

This converter handles positive integers. Negative numbers (two's complement representation) and fractional binary numbers require specialised converters not covered by this tool.

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