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That depends on your ISP and what it promised you in their contract with you and the location you reside at.
You can test your download and upload speed via www.speedtest.net, but know, that they use bits as units, thus a reported speed of 3Mbit/s is actually 0.375 MB/s or 384 KB/s.
But ISPs rate their connections in bits too, thus the promised speed of 16.000 Kb/s on many ads.

My speeds in Berlin in Germany.
 
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