3GB over 300 Mbps — 1 min 25 s
The advertised 300 Mbps caps at 37.5 MB/s, and once addresses and sequence numbers take their share, 35.31 MB/s is left.
- Time it takes
- 1 min 25 s
- Division alone says
- 80 s
- Real speed
- 35.31 MB/s
- What the ad implies
- 37.5 MB/s
- What the file browser shows
- 2.79 GB
- To finish within a minute
- 425 Mbps
- A full day of this
- 3050.4 GB
Narrower than the line
However fast the line, a narrow hop between router and device caps everything. Wi-Fi 5 tops out at 866 Mbps on paper, so it cannot carry a gigabit line, and a gigabit port ends at 1000 Mbps. The figures below are the standards’ maximums; real links run lower.
- Wi-Fi 4 (802.11n)150Mbps
How many streams fit
What happens when the line is shared. Each figure divides the real speed, packaging already removed, by what the service recommends.
- music streaming882
- a video call94
- HD video56
- full HD video35
- 4K video11
Cells that take the same time
Scale the size and the speed by the same factor and the clock does not move. 1 GB over 100 Mbps takes exactly as long as 10 GB over 1000 Mbps.
Nearby cells
Same file, other lines
Same line, other files
How to read this
- These times assume the line stays full from start to finish. A slow server or a shared connection stretches them.
- Small b is bits, capital B is bytes. Divide by eight to get MB/s.
- The speed you actually see is 94.1% of the advertised one — addresses and sequence numbers take the rest.
- Sizes here are decimal. Windows Explorer’s GB is 7% larger than this one.
Frequently asked questions
Q. How long does 3GB take over 300 Mbps?
1 min 25 s. Plain division says 80 seconds; packaging adds the rest.
Q. What speed will I actually see?
35.31 MB/s. The advertised rate divided by eight gives 37.5 MB/s, and addresses and sequence numbers take their share of that.
Q. What would finish it within a minute?
A 425 Mbps line. This one is 300 Mbps.
Q. What size does the file browser show?
2.79 GB — the same file counted in powers of two.