100 in binary
The decimal number 100 written in binary is 1100100. In hexadecimal it is 64, and in octal 144.
| Base | Value |
|---|---|
| Decimal (base 10) | 100 |
| Binary (base 2) | 1100100 |
| Hexadecimal (base 16) | 64 |
| Octal (base 8) | 144 |
How 100 converts to binary
Binary is base 2, so each place is worth twice the one to its right: 1, 2, 4, 8, 16, and so on. Adding up the place values that have a 1 gives back the decimal number:
64 + 32 + 4 = 100
That is why 100 in decimal is 1100100 in binary: it is exactly the set of powers of two that add up to 100. To get the hexadecimal form, group the bits into fours from the right and write each group as one hex digit, which gives 64.
Convert any number
Type any value and watch all three bases update live in the binary converter, or read the theory behind it in the lessons on binary numbers and hexadecimal.
Want to build the circuit that does this? Open the lab and wire up an adder, or follow the free course from a single transistor up to an 8-bit CPU.
Open the binary converter →Frequently asked
What is 100 in binary?
100 in binary is 1100100. That is the sum of the powers of two 64 + 32 + 4, which add up to 100.
What is 100 in hexadecimal?
100 in hexadecimal is 64. You get it by grouping the binary digits 1100100 into fours from the right and writing each group as one hex digit.
How many bits is 100?
100 needs 7 bits in binary (1100100). It fits in a single 8-bit byte.