Download Speed Calculator
First of all notice how most software, including web browsers, measure the download rate in Kilobytes per second (as the picture of the Firefox download window shows). The Internet service providers, on the other hand, declare speed in bits per second. Suppose you have a DSL running at 512 kbps in downstream. The first thing to do is to divide that number by 8 so we transform kilobits (1000 bits) per second into 1000 bytes per second. After that we need to divide the obtained number by 1.024 because we are now talking about data storage, therefore 1 kilobyte must be equal to 1024 bytes and not 1000 bytes as we have assumed for the transmission rate.
So 512 kbps / 8 = 64.000 bytes
then 64.000 bytes / 1.024 = 62.5 Kilobytes/s or kB/s
Internet speed = Download speed
256 kbps = 31.3 KB/s
512 kbps = 62.5 KB/s
1 mbps = 122.1 KB/s
2 mbps = 244.1 KB/s
4 mbps = 488.2 KB/s
Consider you want to download a file large 640 Megabytes. We know this is equal to 655360 kilobytes (640 x 1024), therefore if your Internet speed is 1 Mbps you will download at 122.1 KB/s, meaning it will take 89.5 minutes to download the file completely.
Not reaching these speeds
Perhaps the most common situations that can result in slow Internet service is the present of a virus on your hard drive. Computer viruses can be transmitted in a variety of ways, most commonly through an attachment to an email. The computer virus will integrate into key programs on the hard drive and silently use up a great deal of resources. By diverting some of the resources to running the virus, an Internet service slow down is inevitable. Fortunately, installing virus protection and removal software will help to remove viruses from the hard drive, as well as prevent new ones from infecting the system. As part of the task of preventing slow Internet service from occurring, it is important to make sure the antivirus software is updated regularly.
Download speed is totally dependent on the site from which you are downloading. What is the size of THEIR pipe? Time of day? Net congestion? About a gazillion factors affect actual download speed. And more importantly, computer components can and will affect speed. What's your hard drive's advertised write speed? If it's less than the download speed. .
For instance, you have a 5MB up and down speed. (far fetched to bear with me) That speed is probably only reached when you are talking directly to the other modem, the one at the ISP.
If you decide to download a megga file from somewhere else, you have to bear in mind all the connections necessary to reach that place. Any one of those links could be the cause of what appears to be a slow down. The speed of your download is totally dependent on the speed of the SLOWEST link.
Along with viruses, there is a wide range of programs created to grab control of software on the hard drive and use it without the knowledge of the system owner. Programs of this type are often referred to as Trojans, since they can creep in before they are ever detected. Along with worm viruses, Trojans use up resources and create an Internet slow down that will be noticeable. The typical Trojan is acquired by opening email attachments, allowing the program to grab the address book and begin to send out more infected attachments to every email address on the hard drive. Antivirus software updates usually identify new Trojans and viruses, and can remove them from the system, provided that the Trojan is not configured to shut down the system if removal is attempted.
Spyware and Adware are relatively innocuous programs that silently download when web sites are visited and are used to track the Internet activity of the user. The collected data is normally used in developing marketing campaigns and creating email texts. Unfortunately, spyware and adware also use up resources that can slow the system down a great deal. Removing the programs will reverse the incidence of slow Internet service, and make it easier to enjoy a more robust speed.
One final reason for a slow loading of a web site will have nothing to do with the speed of the connection or the programs running on the hard drive. If the current level of traffic volume to the site is very high, and the server hosting the site cannot handle the traffic, the perception is often that of slow Internet service. However, this is not really a case of a slow Internet connection, but an overwhelmed server. Generally, if the user will simply back off and visit the site at a later time, the site will load much faster on the follow up attempt.
Not all reasons for slow Internet service are due to clandestine programs and viruses infecting the hard drive. In some cases, the ISP is the origin of the Internet slow down. Routers and servers used to provide the service may be overloaded or experience a technical issue that temporarily slows down the speeds provided by the Internet Service Provider. This is true for high-speed solutions as well as for dialup service providers.