Convert between binary, octal, decimal, and hexadecimal.
Free to use, no sign-up required. Number Base is one of 198 tools built into Xenition, alongside a chat that can use them for you.
Converts a whole number between binary, octal, decimal and hexadecimal, for programming, networking and computer science homework.
The input is checked digit by digit against the chosen base, so a 2 in a binary number is rejected instead of being silently cut off. It is then parsed and written out in bases 2, 8, 10 and 16, with hex letters in capitals. Only non-negative whole numbers without a prefix are accepted: enter FF, not 0xFF. Values above 9,007,199,254,740,991 (2^53 − 1) lose precision.
255 in decimal is 11111111 in binary, 377 in octal and FF in hex.
One hex digit is exactly four binary digits, so a byte is always two hex digits. FF is 11111111, which is far easier to read and type.
Add the powers of two where there is a 1, counting from 0 on the right. 1011 is 8 + 0 + 2 + 1 = 11.
You do not have to open Number Base to use it. Ask Xenition in plain language and it runs the right tool, then carries the answer into whatever you are working on — a document, a spreadsheet, a deck.