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In uTorrent when downloading something I see speed around 200 kB/s, however when I did a speed test I got these results where the download speed shows 1.81Mb/s. Can you explain me the differences in the speeds? I thought that 1Mb is = 1024Kb (or 1000Kb since 2007) so my speed test should show 0.2Mb/s?

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up vote 3 down vote accepted

You're confusing bytes (B) with bits (b)

200 kB/s = 200 x 8 kb/s = 1600 kb/s = 1.5625 Mb/s, which is pretty close to what the speed test shows.

And btw, since 2007, to refer to 1024 multiplier (2^10) you use Ki, Mi, Gi, etc... So for example 1024 bytes = 1 KiB. 1000 bytes = 1 KB.

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The difference in prefix was actually a standard that was introduced much earlier than 2007. They were published in IEC 60027-2 Amendment 2 in 1999. They were incorporated into the full revision in 2000. – MaQleod Oct 19 '11 at 16:53
  • kB is kilo bytes
  • Mb is mega bits

1.81 Mb in kB is 226.25

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