About this tool
Convert numbers between binary, octal, decimal, and hex. Saves time when logs, design specs, or infra configs use a different format than your code expects.
Enter the number string you want to convert (for example FF or 1010). Set the source base (2, 8, 10, or 16) and the destination base. Example — Decimal to hexadecimal: try `255 (base 10 → base 16)` and expect something like `FF`.
Only integer conversion via parseInt — decimals and scientific notation are unsupported. See also: Bytes Converter. Runs in your browser — nothing you paste gets uploaded.
How to use
- Enter the number string you want to convert (for example FF or 1010).
- Set the source base (2, 8, 10, or 16) and the destination base.
- Run the conversion and copy the uppercase result for hex/binary dumps.
- Double-check signed or floating values separately — this tool is for integers.
Example
Decimal to hexadecimal
Input
255 (base 10 → base 16)
Output
FF
Limitations
- Only integer conversion via parseInt — decimals and scientific notation are unsupported.
- Bases outside the common 2/8/10/16 set may produce unexpected results depending on input digits.
- Negative numbers and two’s-complement display are not modeled.
Related tools
1Frequently asked questions
What does the Number Base Converter do?
Convert numbers between binary, octal, decimal, and hex. Runs in your browser — no install, no account.
How do I use the Number Base Converter?
Enter the number string you want to convert (for example FF or 1010). Set the source base (2, 8, 10, or 16) and the destination base. Run the conversion and copy the uppercase result for hex/binary dumps. Double-check signed or floating values separately — this tool is for integers.
Is the Number Base Converter free?
Yes. No signup, no usage limits, no paywall.
Does the Number Base Converter upload my data?
No. Processing happens locally in JavaScript. Your input is not uploaded, stored, or logged.
What are the limitations of the Number Base Converter?
Only integer conversion via parseInt — decimals and scientific notation are unsupported. Bases outside the common 2/8/10/16 set may produce unexpected results depending on input digits. Negative numbers and two’s-complement display are not modeled.