Units
Why is my download speed 8 times slower than my internet plan?
÷ 8
Divide your plan's Mbps by 8 to get the MB/s a download window shows, then take off about 5 % for TCP/IP.
It isn't slower: it's a different unit. Your plan is sold in megabits per second (Mbps) and your browser or game store reports megabytes per second (MB/s).
The arithmetic
- A 500 Mbps plan: 500 ÷ 8 = 62.5 MB/s
- Less framing overhead: 62.5 × 0.949 = 59.3 MB/s, the best a download can show
- Some apps (Steam among them) can show MiB/s, which is 4.6 % lower again: 56.6 MiB/s
| Plan speed | Top speed in MB/s | After TCP/IP overhead | In MiB/s |
|---|---|---|---|
| 10 Mbps | 1.25 MB/s | 1.19 MB/s | 1.19 MiB/s |
| 25 Mbps | 3.12 MB/s | 2.97 MB/s | 2.98 MiB/s |
| 50 Mbps | 6.25 MB/s | 5.93 MB/s | 5.96 MiB/s |
| 100 Mbps | 12.5 MB/s | 11.9 MB/s | 11.9 MiB/s |
| 300 Mbps | 37.5 MB/s | 35.6 MB/s | 35.8 MiB/s |
| 500 Mbps | 62.5 MB/s | 59.3 MB/s | 59.6 MiB/s |
| 1,000 Mbps | 125 MB/s | 119 MB/s | 119 MiB/s |
| 2,000 Mbps | 250 MB/s | 237 MB/s | 238 MiB/s |