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Hi so i just got internet a about a month ago and my net speed is 19MB/s, I have tested it on loads of sites they all say the same thing(19MB/s), but it wont use more than around 2MB/s i have tried downloading different ways, and with more than 1 download at a time and I still get capped at about 2MB/s. It affects everything like loading websites and playing games as well. So if I'm downloading (max 2MB/s) and I load up a web page, every thing slows down, the download speed slows and web sites take for ever to load up, what can it be that makes it thus, and speed test say's 19MB/s

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malware - check what sites are accessed when you load a page using a browser. – suspectus May 8 '13 at 13:51
Speed test websites (like usually measure the speed in Mb (mega bit) while download clients usually use MB (mega byte) as 1 byte is 8 bits that could explain the the difference as 19/8 =~2.4 – Simon May 8 '13 at 13:54

Google "19 megabits in megabytes"

19 megabits = 2.37500 megabytes

Megabit (Mb) ≠ Megabyte (MB)

8 bits = 1 Byte

You have a 19Megabits/second internet connection and that gives you a max supposed speed of 2.375 MegaBytes/second = 2.375MegaOctets/sec

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As the other answers said:

Check you are comparing like-for-like (MB vs Mb).

Real-world downloads rarely run as fast as the theoretical maximum for various reasons.

Also, ISPs will cheat on speed tests. When they are throttling your connection, they will whitelist speed test sites.

To get a real measurement, try a test download of a fixed size from a known high performance server.

CacheFly has some sample files on their homepage. This will give you a good idea of the maximum real world speed you are getting. I can download the 100mb file in under 2 mins on my 5mb connection

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It is not uncommon for ISPs to throttle your speed to well below the maximum speed your line will support, either simply because their back-end bandwidth is oversubscribed (so you are throttled by other users' activity), because they implement a "fair use, variable throttle" policy to try stop their back-end getting saturated, or both.

It is also not uncommon for them to exclude know speed-test sites from the hosts to/from which traffic is throttled, so when using one of those places to judge your speed you see an unthrottled result.

Another reason why speedtests don't always show the result of your ISP's traffic shaping is that they often allow short bursts to skip the shaping algorithm, essentially giving interactive users priority over bulk transfers so interactive use is more responsive - depending on how much a speed test transfers to make its estimate it may all fit in this burst amount so not be affected by traffic shaping where a long download would be.


As Simon points out, your wide discrepancy in the figures you see could also be mostly due to a confusion between bits and bytes in the two speed measurements.

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