1. The 8:1 Ratio: Bits vs. Bytes
The single most common confusion in consumer technology is the distinction between a bit (b) and a Byte (B):
- 1 Byte = 8 bits
- Mbps (Megabits per second): Used by Internet Service Providers (ISPs) and speed tests to measure data transmission speed.
- MB/s (Megabytes per second): Used by Steam, PlayStation, Xbox, and file browsers to measure file storage and transfer rates.
Therefore, a 100 Mbps connection transfers a theoretical maximum of 100 ÷ 8 = 12.5 MB/s.
2. Real-World Download Times for Common File Sizes
| File Size | 100 Mbps (12.5 MB/s) | 300 Mbps (37.5 MB/s) | 1 Gbps (125 MB/s) |
|---|---|---|---|
| 10 GB (HD Movie) | ~13.5 min | ~4.5 min | ~1.3 min |
| 50 GB (Game Update) | ~1 hr 7 min | ~22 min | ~6.7 min |
| 100 GB (AAA Game) | ~2 hr 15 min | ~45 min | ~13.3 min |
3. Why Is Your Actual Download Slower?
Real-world transfers rarely reach 100% of line speed due to TCP/IP protocol overhead (~5%–10%), Wi-Fi packet loss, server bandwidth caps on the content delivery network (CDN), and drive write speed limits.