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Bytes to kilobytes

Multiply bytes by 0.001 to get kilobytes.

1 B = 0.001 kBIEC 80000-13
B
10kB

10,000 B = 10 kB

How to convert bytes to kilobytes

The kilobyte is one thousand bytes (10³ B) in the decimal (SI) convention. The byte is eight bits — the basic unit of digital storage.

Worked example — 10,000 B: 10,000 × 0.001 = 10 kB.

Bytes to kilobytes table

Common conversions. The reverse table is on kilobytes to bytes.
BytesKilobytes
500 B0.5 kB
1,000 B1 kB
2,000 B2 kB
5,000 B5 kB
10,000 B10 kB
50,000 B50 kB
100,000 B100 kB
500,000 B500 kB
1,000,000 B1,000 kB

Reverse and related

About bytes and kilobytes

Byte (B)

1 B = 0.001 kB

Definition. Eight bits — the basic unit of digital storage

History and origin

The byte was named in 1956 by Werner Buchholz at IBM, during the design of the Stretch computer, for the group of bits needed to encode one character — respelled from bite so it could not be confused with bit. Eight bits became the standard with the System/360 in the 1960s, giving 256 possible values.

Current use

The byte is the basic unit for file sizes and memory; storage and documents are measured in bytes and their multiples.

Source: IEC 80000-13 (quantities and units — information science); NIST on binary prefixes

Kilobyte (kB)

1 kB = 1,000 B

Definition. One thousand bytes (10³ B) in the decimal (SI) convention

History and origin

The kilobyte took the metric kilo prefix for a thousand, but in computing it was often used loosely for 1024 bytes. The IEC later defined the kibibyte for the binary value to remove the ambiguity.

Current use

Kilobytes measure small files and text documents; in strict decimal use a kilobyte is exactly one thousand bytes.

Source: IEC 80000-13 (quantities and units — information science); NIST on binary prefixes

Where people use this

Bytes: file sizes, memory. Kilobytes: small files, documents. 1000 bytes is 1 kB.

How we know this is right
The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:
1 kB = 1,000 B, so 1 B = 1 ÷ 1,000 = 0.001 kB.

Every value is carried to full double precision; the display is rounded.

Both units are defined in IEC 80000-13 (quantities and units — information science); NIST on binary prefixes.

Questions people ask

How many bytes make a kB?

It takes 1000 bytes to make one kilobyte (decimal).

How many kB is 5000 bytes?

5000 bytes is 5 kB.

How many kB is 2000 bytes?

2000 bytes is 2 kB.

All byte conversions