One number, three number systems

One decimal integer becomes both binary and hex by repeated division: 255 is 11111111 in binary and FF in hex. The page shows all three together because that trio is the working vocabulary of digital logic, memory addresses, and colour codes like #FF5733.

Enter any whole number and read both outputs. Use it to build intuition: powers of two are a single 1 followed by zeros in binary (256 is 100000000), and each hex digit packs exactly four bits — which is why programmers reach for hex over long binary strings.

It converts whole numbers only — no fractions, floats, signed two's-complement forms, or other bases like octal. Fractional and floating-point representations follow different rules entirely.

That is the promise behind every tool here. Files are read in your browser tab, processed there, and discarded when you close it — never uploaded to our servers.