How file size conversion works
This calculator uses decimal storage units, where each larger unit is 1,000 times the previous unit.
1 KB = 1,000 B · 1 MB = 1,000 KB · 1 GB = 1,000 MB
File size example
One gigabyte equals 1,000 megabytes or one billion bytes using decimal units.
GB vs GiB
Binary units such as KiB, MiB and GiB use powers of 1,024 and are different from the decimal units used by this calculator.
Frequently asked questions
How many MB are in one GB?
1,000 MB using decimal units.
How many bytes are in one MB?
1,000,000 bytes using decimal units.
Is GB the same as GiB?
No. GB is decimal while GiB is a binary unit based on powers of 1,024.
Using this calculator effectively
This calculator converts file sizes between decimal bytes, KB, MB, GB and TB. It is useful when storage, transfer or product specifications use different decimal units and you want a consistent comparison.
Common uses
- Converting MB to GB or GB to MB.
- Comparing file sizes with storage or transfer limits.
- Checking decimal storage values before using them in another calculator.
Tips for a better estimate
- Check whether the source uses decimal units such as GB or binary units such as GiB.
- Do not mix GB and GiB as if they were the same quantity.
- Keep enough decimal places when converting a value that will be used in a later calculation.
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