Choose the source and target base to instantly convert binary, octal, decimal, or hexadecimal values.
Fill in the form fields the tool shows.
Change modes or toggles if available.
Copy the generated output when it looks right (often updates live).
Binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16) are the most common number bases in computing. This tool uses arbitrary-precision arithmetic so even very large values convert accurately.
Complete the fields in Number Base Converter. Output is produced in your browser from those inputs — copy it when ready.
Empty optional fields if you want a minimal result. Invalid combinations should surface an error message.
Whenever possible, Number Base Converter processes your data locally with JavaScript in this page. That means drafts, secrets, and unfinished work stay on your device by default. Prefer this workflow when you do not want to upload sensitive text, tokens, passwords, or files to a third-party service.
Yes, both uppercase and lowercase A–F are accepted for hexadecimal values.
A clear error message explains which digits are invalid for that base.
For most FlyUtils tools, no. Processing happens in your browser with JavaScript. If a tool ever needs a server, that will be stated clearly on the page.
Yes. Number Base Converter is free, with no sign-up and no artificial usage caps for normal personal and work use.
Yes. The page is mobile-first, so you can paste input, tweak options, and copy results from a phone or tablet.