Number Base Converter (Binary, Octal, Decimal, Hex)
Free online number base converter. Edit any field — binary, octal, decimal, or hexadecimal — and see the others update live. 100% in your browser.
About Number Base Converter (Binary, Octal, Decimal, Hex)
Enter a number in the binary, octal, decimal, or hexadecimal field and the other three update instantly. You can edit whichever base you have on hand and read off the equivalent in the format you need, without doing the arithmetic by hand.
The conversion happens in your browser with no network request. It is a quick reference when you are reading memory addresses, decoding color values, working with file permissions in octal, or interpreting bit flags during debugging.
Frequently asked questions
- What is the largest number it can convert?
- It handles standard integer values reliably; extremely large numbers may lose precision because of how JavaScript represents numbers.
- Can I enter hex with a 0x prefix?
- Enter the digits themselves in the hexadecimal field; the prefix is a notation convention rather than part of the value.
- Does it support negative numbers?
- It is built for non-negative integer conversion across the four common bases.