Bytes and kilobytes
A byte is eight bits, enough to store one character of ASCII text. File sizes, memory and storage are all counted in bytes and their multiples.
A kilobyte (kB) is 1,000 bytes in the SI decimal system. Small files such as text documents, icons and emails are measured in kilobytes.
Worked example
Convert 2,048 B: 2,048 × 0.001 = 2.048, so 2,048 bytes is 2.048 kilobytes. Likewise 1,000 B = 1 kB.
Estimating in your head
The factor is a power of ten, so just move the decimal point 3 places to the left: 2,048 B = 2.048 kB.
Going the other way
To convert kilobytes to bytes, divide by 0.001 (or multiply by 1,000).
How this works
kB = B × 0.001
1 B = 1 B and 1 kB = 1,000 B, both by definition, so the factor is their ratio: 0.001 exactly. Results drop binary floating-point noise beyond 15 significant digits and display at the precision you choose (6 significant figures by default). Copy result copies the full value.
Frequently asked
How many kilobytes are in a byte?
1 byte = 0.001 kilobytes, exactly. The value follows from the unit definitions, so it never changes.
How do I convert bytes to kilobytes?
Multiply by 0.001. For example, 1,000 B × 0.001 = 1 kB.
What is 10,000 B in kilobytes?
10,000 B = 10 kB. The table next to the converter lists more common values.
Is the result rounded?
Only on screen. The page computes with the exact definitions and removes floating-point noise past 15 significant digits; pick 3 to 12 significant figures, or use Copy result for the full value.
Sources
- NIST — Prefixes for binary multiples (IEC 80000-13)
- BIPM — The International System of Units (SI Brochure), 9th edition
- Wikipedia — Byte
Reviewed Oct 17, 2026 · test vectors fixtures/units/data/bytes-to-kb/