NetTools

Download Time Calculator

File size and connection speed in — download time out, with the bits/bytes conversion handled for you.

File size (MB)

Connection speed (Mbps)

Download time (s)

Connection speed is in megabits per second (Mbps), but file size is usually shown in megabytes (MB) — this converts between the two.

What you entered

File size (MB): 1000Connection speed (Mbps): 100

1
Convert file size to megabits
1000 MB × 8= 8000 Mb
2
Divide by connection speed
8000 ÷ 100 Mbps= 80 s

Result

Download time (s): 80

A 1000 MB file at 100 Mbps takes about 80 seconds.

Download time by file size and connection speed

File sizes are in megabytes and connection speeds in megabits, so the conversion multiplies by 8. A 100 MB file is 800 megabits.

File size	Speed	Time	In minutes
100 MB	10 Mbps	80.0 s	1.3 min
100 MB	100 Mbps	8.0 s	0.1 min
1,000 MB	10 Mbps	800.0 s	13.3 min
1,000 MB	100 Mbps	80.0 s	1.3 min
5,000 MB	100 Mbps	400.0 s	6.7 min
50,000 MB	1,000 Mbps	400.0 s	6.7 min

These are theoretical times at full line rate. Protocol overhead, server limits, and contention typically make real transfers 10-20% slower.

Megabits vs. megabytes — the classic mix-up

Internet speeds are advertised in megabits per second (Mbps), but file sizes are shown in megabytes (MB) — since there are 8 bits in a byte, a '100 Mbps' connection downloads at roughly 12.5 MB/s, not 100 MB/s.

Real-world speeds are usually lower

Advertised connection speed is a theoretical maximum — actual download speed is often lower due to network overhead, server-side limits, and other traffic sharing the connection, so treat this as a best-case estimate.

Frequently asked questions

I have a 100 Mbps connection — how long to download a 4 GB game?

At 100 Mbps (about 12.5 MB/s), a 4 GB file takes roughly 5 minutes and 20 seconds in the best case. Real-world speeds are typically 70-80% of the rated maximum, so expect closer to 7 minutes.

Why is my download slower than my internet speed suggests?

Internet speeds are advertised in megabits (Mb), but file sizes are in megabytes (MB) — 8 bits per byte. A '100 Mbps' connection downloads at about 12.5 MB/s, not 100 MB/s. Server throttling and network congestion also reduce real throughput.

How does this differ from the data transfer rate calculator?

This tool predicts download time from file size and connection speed. The data transfer rate calculator works backward — you time an actual transfer and it tells you the real throughput achieved.