Download Time Calculator
File size and speed to time
File & Connection
Wi-Fi or busy servers: 50–80%
Estimated download time
22m 14s
Data in bits-
Time at Other Speeds
| Speed | Time |
|---|
Download Times by File Size (theoretical)
| File | 100M | 500M | 1G |
|---|---|---|---|
| 100 photos (500 MB) | 40s | 8s | 4s |
| HD movie (4 GB) | 5m 20s | 1m 4s | 32s |
| 4K movie (20 GB) | 26m 40s | 5m 20s | 2m 40s |
| Large game (100 GB) | 2h 13m 20s | 26m 40s | 13m 20s |
| 1 TB backup | 22h 13m 20s | 4h 26m 40s | 2h 13m 20s |
Connection speeds are in bits (Mbps) while file sizes are in bytes (MB) — a factor of 8. A 300 Mbps line tops out at 37.5 MB/s. Windows reports sizes in GiB (1,024³ bytes), about 7% more than GB.
Formulas & Sources
- Time = size (bytes) × 8 ÷ (speed in bps × efficiency)
- MB, GB, TB use powers of 1,000 (SI); MiB and GiB use powers of 1,024 (IEC)
Last reviewed: 2026-10-19
FAQ
How long does 100 GB take on a 1 Gbps connection?
About 13m 20s in theory; Wi-Fi and server limits usually make it longer.
What's the difference between Mbps and MB/s?
Mbps is megabits per second; MB/s is megabytes per second. 1 byte = 8 bits, so 300 Mbps is 37.5 MB/s.
Why does Windows show a different file size?
Windows counts 1 GB as 1,073,741,824 bytes (a GiB). Choose GiB to match what Windows shows.
How fast is 100 Mbps really?
Up to 12.5 MB/s — a 4 GB movie takes about 5 and a half minutes at full speed.
Why are my downloads slower than my plan?
Wi-Fi signal, router limits, other devices and server throttling all reduce speed. A wired connection gets closest to your plan.