How to Convert KB to MB and GB (1,024 or 1,000?)

Step-by-step

1. Enter the size and choose the unit you are converting from, such as KB.
2. Choose the unit you want, such as MB, or use the KB to MB or MB to GB buttons.
3. Pick the binary standard (1 KB = 1,024 bytes) or the decimal standard (1 KB = 1,000 bytes).
4. Read the result and the list showing the same size in every unit.
5. Use the same standard throughout a calculation so the numbers stay consistent.

Binary and decimal units

In the binary system, 1 MB is 1,024 KB and 1 GB is 1,024 MB, so a 5 MB file is 5,120 KB. In the decimal system, 1 MB is 1,000 KB and 1 GB is 1,000 MB, so the same file is 5,000 KB. Strictly, the binary units are called KiB, MiB and GiB, although many systems still label them KB, MB and GB.

Why a new drive shows less space

Drive makers use decimal units. A 500 GB drive holds 500,000,000,000 bytes. A system that divides by 1,024 three times shows that as about 465.66 GB, which is why the drive looks smaller than advertised. No space is missing, it is the unit that differs.

Planning storage

To estimate total storage, multiply the number of files by their average size, then convert to the unit you need. The Storage Calculator does this and shows the result in MB, GB and TB.