Mbps vs MB/s: the difference that fools everyone
Internet speeds are expressed in megabits per second (Mbps), while file sizes are in megabytes (MB) or gigabytes (GB). One byte is 8 bits, so a 100 Mbps connection downloads at best 12.5 MB per second. That is why a program shows "11 MB/s" on 100 Mbps fibre: it is normal.
The calculation
Time = file size × 8 ÷ speed. We add about 10% for network protocols. Example: a 100 GB game on 200 Mbps fibre takes about 1 h 14 min.
Why a download can be slower
- The remote server (game store, download site) often limits its speed.
- Wi-Fi reduces the real speed: compare with a cable test.
- Other devices in the home share the same connection.
To know your real speed, run a test. To choose the right plan, use our questionnaire.
Frequently asked questions
Why does my download show 12 MB/s on 100 Mbps fibre?
Because 100 megabits per second equals 12.5 megabytes per second. That is the theoretical maximum, so 11 to 12 MB/s is an excellent result.
Is the calculation exact?
It is an estimate. The real speed also depends on the source server, Wi-Fi and simultaneous use of the connection.