gizmobench

Bytes to KB Converter

Bytes to KB is one division, and the number you divide by depends on which KB you mean: 1,024 bytes to the binary KB, properly the kibibyte (KiB), which is what Windows and most file managers report, and 1,000 bytes to the decimal kilobyte (kB) that the SI defines and drive makers print. This page opens with Byte in the From box and Kibibyte in the To box, ahead of whatever pair the converter last remembered, so 1,024 bytes reads 1 KiB, 4,096 bytes reads 4 KiB and 1,048,576 bytes reads 1,024 KiB, which is one mebibyte. The decimal answer is never hidden behind a setting: the list under the headline prints the same byte count in bits, kB, MB, GB, TB, KiB, MiB, GiB and TiB together, so 5,000 bytes shows as 4.8828125 KiB and as exactly 5 kB on one screen. Nothing in this category is tucked behind a switch, so every one of those units is on the page at once. The swap button between the two boxes reverses the pair into kibibytes to bytes, where 1 KiB is 1,024 B.

To0.0009765625
Category
Digital storage
Base unit
byte

1 B in every digital storage unit

  • Bitbit
    8
  • KilobytekB
    0.001
  • MegabyteMB
    0.000001
  • GigabyteGB
    1e-9
  • TerabyteTB
    1e-12
  • KibibyteKiB
    0.0009765625
  • MebibyteMiB
    9.536743e-7
  • GibibyteGiB
    9.313226e-10
  • TebibyteTiB
    9.094947e-13

Common questions

How many bytes are in a KB?
It depends on which KB, and both are on this page. The binary KB, properly the kibibyte (KiB), is 2 to the 10th power, so 1,024 bytes, and that is what Windows and most file managers mean when they write KB. The decimal kilobyte (kB) is 1,000 bytes, the SI reading of the kilo prefix. The binary figure doubles the way you would expect: 2,048 B is 2 KiB, 4,096 B is 4 KiB, 10,000 B is 9.765625 KiB and 1,048,576 B is 1,024 KiB, which the same list shows as 1 MiB.
What is the formula for bytes to KB?
KiB = bytes / 1,024 for the binary reading, and kB = bytes / 1,000 for the decimal one. This page arrives with the binary reading in the To box, and choosing Kilobyte (kB) in that menu moves the headline to the decimal one, though you do not have to: both already appear in the list under the answer. Going the other way, bytes = KiB x 1,024 and bytes = kB x 1,000, and the swap button between the boxes sets that direction up for you.
Worked example: how many KB is 5,000 bytes?
4.8828125 KiB, and exactly 5 kB in decimal. Type 5,000 into the From box, with or without the comma, and 5e3 is read the same way. The list underneath gives the rest of the same size, including 40,000 bits and 0.005 MB. Other sizes work out the same way: 2,500 B is 2.44140625 KiB, 1,500,000 B is 1,464.84375 KiB and 1,000,000 B is 976.5625 KiB, 1,000 kB and exactly 1 MB.
What is 1 byte in KB?
0.0009765625 KiB, which is 1 divided by 1,024, and 0.001 kB in decimal. Neither needs exponential notation, because both stay above a millionth. From there, 100 B is 0.09765625 KiB, 500 B is 0.48828125 KiB and 1,000 B is 0.9765625 KiB, which is the whole disagreement in one line: a thousand bytes is one decimal kilobyte but only 0.9765625 binary ones.
Why does the menu say Kibibyte rather than KB?
Because KB is ambiguous and kibibyte is not. The IEC names, KiB, MiB, GiB and TiB, mean the binary units exactly, while kB, MB, GB and TB mean the decimal ones, and this page opens on the binary pair because that is what an operating system usually means when it labels a file KB. The two families separate further as the unit grows: 2.4 percent between kB and KiB, 4.9 percent between MB and MiB and 7.4 percent between GB and GiB, which is why the gap only becomes obvious at drive sizes.
Is kb with a small b the same as KB?
No. A kilobit is 1,000 bits and a byte is 8 bits, so the Bit row under the answer is the one to read for it: 1,000 B is 8,000 bit, which is 8 kilobits, and 1,024 B is 8,192 bit. Network and transfer speeds are normally quoted in kilobits or megabits per second while file sizes are quoted in kilobytes, so a factor of 8 sits between the two figures before any binary or decimal question arises.
Can I convert KB back to bytes here?
Yes. The swap button between the two boxes reverses the pair, so the page becomes kibibytes to bytes: 1 KiB gives 1,024 B, 2 KiB gives 2,048 B, half a kibibyte gives 512 B and 1,024 KiB gives 1,048,576 B. To work in decimal kilobytes instead, choose Kilobyte (kB) in the From menu after swapping, where 1 kB is 1,000 B and 1 KiB is 1.024 kB.
How are the smallest rows printed?
Results are shown to twelve significant digits with trailing zeros dropped, and anything below a millionth switches to exponential notation rather than a run of leading zeros. So 1,024 B reads 1.024e-9 TB, 9.536743e-7 GiB and 9.313226e-10 TiB in the list, while the rows a person actually reads stay decimal: 1.024 kB, 0.001024 MB and 0.0009765625 MiB. Digits are grouped with commas for display, and Copy result copies the figure without them, as does the Copy button on each row.
Why does the page open on bytes and kibibytes when I last converted something else?
Because a page that names a pair should show that pair. This one sets Byte and Kibibyte on arrival, ahead of whatever the converter last remembered, and it leaves the main unit converter alone: go back to the converter itself and it is still on the pair you left it on. The number you last typed does travel with you, since it is usually the one you are still working on. Nothing is uploaded: the factors ship with the page, so it keeps working with no network connection once the page has loaded.

Conversion factors are the exact legal definitions where one exists. An inch is exactly 2.54 cm and a pound exactly 0.45359237 kg, so those conversions are exact rather than approximate. Temperature uses offsets rather than factors, and that is shown in the working.