Convert bits to bytes
8 bits make 1 byte, because every byte is made of 8 bits. Type the number of bits and the converter divides it by 8 and shows the result in bytes (B).
What is a bit, and what is a byte?
A bit is a binary digit, a single 0 or 1, and the most basic unit of information in computing[1]. One bit settles one two-way question, such as whether a pixel in a black-and-white image is black or white.
A byte is a group of 8 bits[2], so a byte is eight times bigger than a bit. Eight bits give 256 different patterns of zeros and ones, which lets one byte store a whole number from 0 to 255[2].
The symbol for the bit is “bit” under the IEC 80000-13 standard, while IEEE 1541 allows a lowercase “b” that is easy to mix up with “B” for byte[1]. That is why 500 Kb sometimes means kilobits and sometimes kilobytes.
How do you convert bits to bytes?
Divide the number of bits by 8, because that is how many bits each byte holds. The formula is bytes = bits ÷ 8. For example, 64 bits are 64 ÷ 8 = 8 bytes, and 100 bits are 12.5 bytes.
The converter shows the exact result, fractions included. In a computer’s memory, though, data takes up whole bytes, because in many computers the byte is the smallest piece of memory with its own address[2]. A single 12-bit value stored on its own therefore uses 2 bytes, even though the arithmetic gives 1.5.
How many bytes is a given number of bits?
| Bits | Bytes |
|---|---|
| 1 bit | 0.125 B |
| 4 bits | 0.5 B |
| 8 bits | 1 B |
| 12 bits | 1.5 B |
| 16 bits | 2 B |
| 24 bits | 3 B |
| 32 bits | 4 B |
| 64 bits | 8 B |
| 100 bits | 12.5 B |
| 128 bits | 16 B |
| 256 bits | 32 B |
| 512 bits | 64 B |
| 1,000 bits | 125 B |
| 1,024 bits | 128 B |
| 4,096 bits | 512 B |
| 8,192 bits | 1,024 B |
| 1,000,000 bits | 125,000 B |
Which data sizes are given in bits?
| What it is | Bits | Bytes |
|---|---|---|
| Nibble, one hexadecimal digit | 4 bits | 0.5 B |
| IPv4 address, such as 192.168.1.1 | 32 bits | 4 B |
| IPv6 address | 128 bits | 16 B |
| AES-128 encryption key | 128 bits | 16 B |
| AES-256 encryption key | 256 bits | 32 B |
| Block of data encrypted by AES | 128 bits | 16 B |
| Java int integer | 32 bits | 4 B |
| Java long integer | 64 bits | 8 B |
| Java char character | 16 bits | 2 B |
Why does a byte have 8 bits?
At first the byte had no fixed length. Werner Buchholz coined the word in 1956 while IBM was designing its Stretch computer[8]. Early computers stored characters in 4-bit and 6-bit codes, and in 1963 the ASCII code extended a character to 7 bits[2].
Stretch itself was the first computer to use 8-bit bytes, and the machine left IBM for the Los Alamos laboratory in April 1961[8]. The size stuck because the IBM System/360 family, which stored characters in the 8-bit EBCDIC code, became so widespread[2]. In the 1970s, 8-bit microprocessors such as the Intel 8080 made it widespread[2]. Donald Knuth noted that since about 1975 the word byte has meant exactly eight binary digits[2].
Eight is also a handy power of two: 28 gives 256 values, and a byte splits into two 4-bit nibbles, each written as one hexadecimal digit[2]. That is why a byte in hexadecimal always has two digits, from 00 to FF.
Which ways of typing bits does this converter accept?
| What you type | What the converter shows | How we read it |
|---|---|---|
| 1.5 kbit | 187.5 B | The point marks the decimal part and kbit is a kilobit, 1000 bits, so the field holds 1500 bits. |
| 1,5 kbit | 187.5 B | A comma before a single digit is a decimal comma, as in much of Europe, so the field also holds 1500 bits. |
| 1,500 | 187.5 B | A comma before three digits separates the thousands, so the field holds one thousand five hundred bits. A hint below the field confirms how we read it. |
| 1 500 | 187.5 B | A space between the thousands is ignored, so the field holds one thousand five hundred bits. |
| 64 bits | 8 B | The field’s own unit pasted with the number does no harm, because we take the number in front of it. |
| 64-bit | 8 B | The hyphenated form from a processor or operating system description also reads as 64 bits. |
| 2 kbit | 250 B | Kilobits go into the field as 2000 bits, with a note below it. |
| 1 Mbit | 125000 B | A megabit is a million bits, so the field stores 1000000 bits and says so below it. |
| 2 bytes | 2 B | Bytes pasted into the bits field become 16 bits, with a note below it, so the result is the same 2 bytes again. |
| 3/4 | 0.094 B | A fraction with a slash counts as three quarters of a bit, and the result is rounded to three decimal places. |
| 1e6 | 125000 B | Scientific notation from a spreadsheet is read as it stands: 1e6 is a million bits. |
Convert other units to Bytes
Convert Bits to other units
Sources
- Bit — Wikipedia
- Byte — Wikipedia
- DDR3 SDRAM — Wikipedia
- RFC 791: Internet Protocol — RFC Editor
- RFC 8200: Internet Protocol, Version 6 (IPv6) Specification — RFC Editor
- FIPS 197: Advanced Encryption Standard (AES) — NIST
- The Java Language Specification, section 4.2 — Oracle
- Timeline of the IBM Stretch/Harvest Era (1956–1961) — Computer History Museum
Every figure in the tables was computed from the unit definitions and checked arithmetically before publication. Historical values and the names of local units come from the sources listed above.
Content last reviewed: · written and checked by the Arteon team
Frequently asked questions about bits and bytes
Does a byte have more bits on a 64-bit system?
No. A byte has 8 bits on a 64-bit system too. The 64 describes the word size, the chunk of data the processor works on at once, which is 8 bytes. On a 32-bit system the word is 4 bytes[2].
How many megabytes per second is a 100 Mbps connection?
At most 12.5 MB per second, because connection speeds are quoted in megabits and 100 ÷ 8 = 12.5. Any other speed works the same way: divide the number of megabits per second by 8.
Have a question or suggestion?
If you spot a mistake in a table or miss a conversion, write to us.