Free Number Base Converter (Binary, Octal, Hex)
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About the Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal — type in any base and see all others update live, all in your browser.
How to use the Number Base Converter
- 1Type a number into any of the four fields — binary, octal, decimal or hexadecimal.
- 2All other bases update instantly as you type.
- 3Click the copy icon next to any field to copy that value.
- 4Clear all fields with the Reset button to start fresh.
Frequently asked questions
What are the four number bases?
Binary (base 2) uses digits 0–1; octal (base 8) uses 0–7; decimal (base 10) is our everyday system; hexadecimal (base 16) uses 0–9 and A–F.
How large a number can I convert?
The converter uses JavaScript's built-in BigInt so it handles arbitrarily large integers with no precision loss. Standard 64-bit integers and beyond are supported.
Are negative numbers supported?
Yes — prefix the decimal input with a minus sign. The other bases will display the corresponding negative value.
Why are letters used in hexadecimal?
Hexadecimal needs 16 symbols. After 0–9 are used up, the letters A–F represent values 10–15. Both uppercase (A–F) and lowercase (a–f) are accepted as input.
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