As computers have become a more ingrained part of society, the ability for home and small offices to link multiple users to a single Internet connection has grown. Many users sharing the same connection can affect Internet speeds, depending on a number of factors, including the type of Internet usage and the network’s available bandwidth. 

If you are connected wirelessly through your home router, then you should see much less speed, as those cheap routers dont have enough transmitting power to show you your actual speeds.

The best is tested in wired computers to a LAN switch or router.

For example, you have 5 computers in your office and you have a 10Mbps internet connection.

If all 5 computers have on to the internet, that means all the computers are using some chunk from the 10Mbps plan. And you never know, whats happening or getting used in your computers in the background. That may be windows updates, or kernel updates, anti virus updates, application updates, etc.

And if a computer is downloading a torrent and using up around 9Mbps, then you have like 1Mbps left to get shared with your 4 other computers. And then if you do a speedtest, you should get around 0.2Mbps or 0.3Mbps. So, basically, whatever is left, you get.

If you are really looking to test your internet speed, then you should first switch off all the computers and only connect or switch on one single computer and then do a speedtest at www.speedtest.net

You will get accurate of what you are getting from your ISP. If its a 10Mbps Broadband Plan you have, you should normally see something between 6 to 10Mbps. If you have a Leased Line plan of 10Mbps, then you should get speedtest of 9-10Mbps dedicated.

The internet speed do not decrease,the bandwidth only gets shared among the pcs that share the same internet connection. If you want the bandwith to be equally shared among all computers, you will need a dedicated leased line plan and a professional setup to be done, which would cost a bit. 

For example, you go for a 10Mbps Leased Line Plan and you have 5 computers in your office, and you need each system to get 2Mbps dedicated only, then we can design the solution for you too. It costs for network design, hardware purchase, deployment, testing. So, its only for those who are serious about it.