About This Converter
This free online binary, hexadecimal, and decimal converter lets you
instantly switch between the four most common number bases: base-2
(binary), base-8 (octal), base-10 (decimal), and base-16
(hexadecimal). Just type in any field and all others update live.
Beyond simple conversion, this tool shows you a
bit-map visualization (great for understanding how
memory works), an ASCII character lookup for values
0–127, and a step-by-step breakdown of the
decimal-to-binary algorithm — useful for learning and teaching.
All computation happens in your browser. No data is sent to any server
— fully private, fully offline-capable.
Frequently Asked Questions
How do I convert decimal to binary?
Repeatedly divide the decimal number by 2 and record the remainders.
Read the remainders from bottom to top. For example, 13 → 1101 in
binary. Use this tool to see each step automatically.
What is hexadecimal used for?
Hexadecimal (base 16) is used extensively in computing — from color
codes (#FF5733) to memory addresses, bytecode, and cryptographic
hashes. It's compact: one hex digit represents exactly 4 bits.
What is the maximum number supported?
This tool handles integers up to 2^53 − 1 (JavaScript's safe integer
limit, over 9 quadrillion). For most practical tasks — including
32-bit and 64-bit values — this is more than sufficient.
What is ASCII and how does it relate to binary?
ASCII maps characters (letters, digits, symbols) to numbers 0–127.
Since computers store everything as binary, the letter 'A' is stored
as 65 decimal = 01000001 binary. This converter shows you the ASCII
character for any value in that range.