Bits to Bytes
Enter a number of bits and read the size in bytes. A byte holds 8 bits, so the converter divides by 8 and keeps any fraction.
Formula: B = bit × 0.125
- Byte (B)
- Also called octet
- A group of 8 bits, the smallest amount of memory a computer gives its own address. One byte can hold 256 different values, from 0 to 255, which is enough for one letter of plain English text.
Bits to bytes table
| Bits (bit) | Bytes (B) |
|---|---|
| 1 | 0.125 |
| 2 | 0.25 |
| 3 | 0.375 |
| 4 | 0.5 |
| 5 | 0.625 |
| 6 | 0.75 |
| 7 | 0.875 |
| 8 | 1 |
| 9 | 1.125 |
| 10 | 1.25 |
| Bits (bit) | Bytes (B) |
|---|---|
| 12 | 1.5 |
| 15 | 1.875 |
| 20 | 2.5 |
| 25 | 3.125 |
| 30 | 3.75 |
| 40 | 5 |
| 50 | 6.25 |
| 60 | 7.5 |
| 75 | 9.375 |
| 100 | 12.5 |
Why eight bits
Early machines used bytes of six, seven or nine bits, depending on the character set they were built for. The eight-bit byte won out in the 1960s and 1970s because it fits one character of an extended alphabet and splits evenly into two four-bit halves, which suits hexadecimal notation: every byte is exactly two hex digits, from 00 to FF.
Network standards still say octet when they mean exactly eight bits, so a protocol document stays unambiguous even on hardware that once used other sizes. In everyday use, byte and octet are the same thing.
Where you meet bits and where you meet bytes
Speeds are counted in bits per second: internet plans, Wi-Fi links, USB and Ethernet ports. Sizes are counted in bytes: files, photos, memory cards and drives. That split is why a download meter and a file manager seem to disagree until you divide by 8.
For larger network figures, megabits to MB does the same division with the prefixes included, and KB to MB moves between byte sizes once you have them.
Nibble
Half a byte, 4 bits. One hexadecimal digit stands for exactly one nibble.
Word
The block of bits a processor handles in one step, today usually 32 or 64 bits, so 4 or 8 bytes.
Kilobit
1,000 bits, written kbit or kb. It equals 125 bytes, not 1,000 bytes.
One bit in other data units
One bit in every other data size unit on this site
- Bytes0.125 B
- Kilobytes0.000125 KB
- Megabytes1.25E-7 MB
- Gigabytes1.25E-10 GB
- Terabytes1.25E-13 TB
- Megabits0.000001 Mbit
Bits and bytes questions
How many bits make one byte?
Eight. Modern computers group bits in sets of eight, called octets in networking standards, and treat each set as one byte.
Is a lowercase b a bit or a byte?
By convention a lowercase b means bit and an uppercase B means byte, so 100 Mb/s is a line speed in bits and 100 MB is a file size in bytes. The two differ by a factor of 8.
How many bytes is 64 bits?
64 bits is 8 bytes. That is the width of a 64-bit number or memory address in a modern processor.
Can a value in bits give a fraction of a byte?
Yes. 12 bits is 1.5 bytes. Storage is always allocated in whole bytes, so a 12-bit value really occupies 2 bytes on disk, but the arithmetic itself allows halves and quarters.
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