Download Time Calculator
Enter a file size and your internet speed — see exactly how long the download will take.
Mbps vs MBps — the source of all confusion
The single biggest reason downloads feel "slower than advertised" is the difference between bits and bytes. Internet plans are sold in megabits per second (Mbps), but files and download managers are measured in megabytes per second (MBps or MB/s). There are 8 bits in 1 byte, so you divide your plan speed by 8 to get the real-world download rate.
Common download times at 100 Mbps
A quick reference for a typical 100 Mbps fibre connection (a real-world rate of about 12.5 MB/s, ignoring overheads).
| File | Approx. size | Time at 100 Mbps |
|---|---|---|
| Song (MP3) | 5 MB | 0.4 s |
| Photo (high-res) | 10 MB | 0.8 s |
| App / PDF | 100 MB | 8 s |
| HD movie | 2 GB | 2 min 44 s |
| 4K movie | 15 GB | 20 min 30 s |
| PC game | 50 GB | 1 h 8 min |
| Backup archive | 1 TB | ~23 h 18 min |
Frequently asked questions
Why is my download slower than my plan speed?
Two reasons. First, plans are in megabits (Mbps) but downloads display in megabytes (MB/s) — divide by 8. A 100 Mbps plan tops out at 12.5 MB/s. Second, real speeds run at roughly 80–90% of the maximum because of Wi-Fi loss, network overhead, and limits on the server you are downloading from.
How do I convert Mbps to MB/s?
Divide by 8. 40 Mbps = 5 MB/s, 100 Mbps = 12.5 MB/s, 1000 Mbps (1 Gbps) = 125 MB/s. The lowercase b means bits and the uppercase B means bytes — eight bits make one byte.
How long does it take to download a 1 GB file?
On 100 Mbps it takes about 80 seconds at the theoretical maximum (1 GB = 8000 megabits, divided by 100 Mbps). On a 50 Mbps connection it is roughly 2 min 40 s, and on 1 Gbps it is about 8 seconds. Add 10–20% for real-world overhead.
Does this calculator use MB = 1000 or 1024?
It uses the decimal standard where 1 GB = 1000 MB and 1 TB = 1000 GB, which is how internet plans and most download tools quote sizes. Some operating systems use binary (1024) units, so figures may differ slightly.
What speed do I need to stream 4K video?
Streaming services recommend about 25 Mbps for stable 4K. Downloading is different from streaming — streaming only needs enough bandwidth to keep ahead of playback, while a download uses all available speed to finish as fast as possible.