Hex numbers appear in colour codes, memory addresses, MAC addresses and error codes. This converter turns hex into decimal, binary and octal, and handles very long values exactly.
How to use the Hexadecimal Converter
- Number
- Input base
- Convert to
- Two’s complement width
Everything runs in your browser, so results appear instantly and nothing you type is sent to a server.
How it works
The number is read exactly using arbitrary-precision integers (so very long values are not rounded), then written in each base. Two’s complement shows how a negative number is stored in the chosen number of bits.
Formula
value = Σ digit × base^positionTo convert: divide repeatedly by the new base and read the remainders in reverse.Worked example
Inputs — Number: FF5733; Input base: Hexadecimal (16); Convert to: Decimal (10); Two’s complement width: No fixed width.
Results — Result = 16734003; Binary = 1111 1111 0101 0111 0011 0011; Octal = 77653463; Decimal = 16,734,003; Hexadecimal = FF5733; Bits needed = 24.
Key terms
- Bit
- A binary digit, 0 or 1.
- Nibble
- Four bits, one hexadecimal digit.
- Two’s complement
- The standard way computers store negative integers.
Frequently asked questions
What is 255 in binary?
1111 1111.
What is FF in decimal?
255.
How do I convert binary to hex by hand?
Split the bits into groups of four from the right and replace each group with its hex digit (0000 = 0 … 1111 = F).
What formula does the Hexadecimal Converter use?
value = Σ digit × base^position.