Downloads
How long does it take to download 100 GB at 50 Mbps?
4 h 41 min
to download 100 GB at 50 Mbps, best case. Typical: 5 h 33 min (at 80 % efficiency, our estimate for Wi-Fi and busy servers).
At 50 Mbps a 100 GB download is an overnight job. Starting it before bed is the practical answer.
The arithmetic
- 100 GB × 8 bits per byte = 800 gigabits (800,000,000,000 bits)
- 50 Mbps = 50,000,000 bits per second = 6.25 MB/s at most
- 800,000,000,000 ÷ 50,000,000 = 16,000 s = 4 h 27 min with zero overhead
- TCP/IP and Ethernet framing use about 5 % of the line (1,460 data bytes per 1,538 on the wire): 16,000 ÷ 0.949 = 4 h 41 min
If the size is really 100 GiB (some stores and Windows label GiB as GB), it is 7.4 % bigger: 5 h 2 min best case.
| Speed | Best case (95 %) | Typical (80 %, estimate) |
|---|---|---|
| 10 Mbps | 23 h 25 min | 27 h 47 min |
| 25 Mbps | 9 h 22 min | 11 h 7 min |
| 50 Mbps | 4 h 41 min | 5 h 33 min |
| 100 Mbps | 2 h 20 min | 2 h 47 min |
| 300 Mbps | 46 min 49 s | 55 min 33 s |
| 500 Mbps | 28 min 5 s | 33 min 20 s |
| 1,000 Mbps | 14 min 3 s | 16 min 40 s |
Sources and assumptions
- Overhead: 94.9 % efficiency from TCP/IPv4 on 1,500-byte Ethernet frames (computed); 80 % 'typical' is our estimate.