Uses decimal units: 1 GB = 1,000 MB. That matches drive labels and most provider plans.
Data & storage
File Size Converter
Convert KB, MB, GB and TB in one go. Type a number and see all the units side by side.
Short answer: 1 GB is 1,000 MB, 1 MB is 1,000 KB and 1 TB is 1,000 GB when you use decimal units, the same ones used on drive boxes and internet plans.
Why do sizes sometimes look smaller on my computer?
Some operating systems count in powers of 1,024, so a drive labelled 500 GB can show as about 465 GB. The drive is not missing space; the two systems just count differently. Technically the 1,024 units are called KiB, MiB, GiB and TiB, though many programs do not show the “i”.
Handy reference
| Item | Rough size |
|---|---|
| Phone photo | 3 to 5 MB |
| Song (MP3) | 4 to 8 MB |
| 1 hour HD video | about 3 GB |
| Modern game | 50 to 150 GB |
| Laptop drive | 256 GB to 2 TB |
Want to know how long a file of any size will take to download? Use the Download Time Calculator.
FAQ
Frequently asked questions about the File Size Converter
How many MB are in a GB?
1,000 MB in the decimal system (1,024 in the binary system, properly called MiB per GiB).
Why does my 1 TB drive show 931 GB?
Your computer counts in 1,024s while the maker counts in 1,000s. 1 TB is about 931 GiB, so nothing is missing.
Which is bigger, KB or MB?
MB. A megabyte is 1,000 kilobytes.
How many photos fit in 1 GB?
Around 200 to 300 phone photos at 3 to 5 MB each.
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Use this toolResults are estimates for planning. Last reviewed 2 October 2026.