Number Base Converter
Convert between binary, octal, decimal and hexadecimal in real time. Edit any field. No sign-up.
Built by
Miguel Ángel Colorado Marin
Built by
Miguel Ángel Colorado Marin
Full-Stack Developer · Guadalajara, España
I develop web apps, digital tools and full projects — from design to deployment.
How to use the number base converter?
- 1
Select your base field
There are four fields: Decimal (base 10), Binary (base 2), Octal (base 8) and Hexadecimal (base 16). You can start typing in any of them. Each field only accepts valid digits for its base.
- 2
Type or paste the number
Enter the number in the source base field. The converter automatically validates characters: the binary field only accepts 0 and 1, octal accepts 0-7, decimal accepts 0-9 and hexadecimal accepts 0-9 and A-F.
- 3
All fields update simultaneously
As soon as you enter a valid value, the other three fields show the conversion instantly. No button press needed: the conversion is completely bidirectional and real time.
- 4
Copy the result
Each field has a copy button in the upper right corner. Click the icon to copy the value to the clipboard. The summary at the bottom shows all values together in a compact format.
Frequently asked questions
What is the binary system used for?
The binary system (base 2) is the fundamental language of computers. All digital information is stored internally as combinations of 0s and 1s. It is used for low-level programming, bitwise operations, network protocol analysis and understanding data structures at the bit level.
When is hexadecimal used?
Hexadecimal (base 16) is widely used in programming because each hex digit corresponds exactly to 4 bits, making the representation more compact. It is used for CSS color codes (#FF5733), memory addresses, register values, cryptographic hashes and binary code debugging.
What is the octal system used for?
The octal system (base 8) is mainly used in Unix/Linux systems for file permissions (chmod). For example, chmod 755 translates to binary as 111 101 101, which corresponds to rwxr-xr-x. It is also used in some embedded systems and older programming languages.
Can this tool convert negative numbers?
Currently the tool works with non-negative integers. For negative numbers in programming, special representations such as two's complement are used, which depend on word size (8, 16, 32 or 64 bits) and go beyond a simple base conversion.
Is there a limit on the size of the number?
The tool uses JavaScript's BigInt for conversions, so it can handle arbitrarily large integers, beyond the Number limit (2^53-1). The only practical limit is browser memory.
Embed the converter on your site
Embed this number base converter in any web page with a simple iframe:
<iframe
src="https://miguelacm.es/embed/number-base"
width="100%"
height="600"
frameborder="0"
title="Number Base Converter"
></iframe>