I am sure this is easy but its late here and I cant think straight. I am need a formula that I can use to calculate potential bandwidth usage. The reason I am looking into this is because I am one that does not believe in the unlimited world. So I want to be able to show a potential client that just because its offered they have no use for unlimited bandwidth or space. One of my sites is under 100 MB and has the bandwidth set at 5000 MB.

So I am needing a formula so I can see the number of potential clients they could get before hitting thier band width.

I guess this is hard because I dont understand how exactly bandwidth is calculated. Would that mean with the above numbers that if one person visited their site then they would use 100 MB towards the bandwidth quota?


And a second question. I know that their are a lot of variables to consider but what is the average size of a small business site with about 5-8 pages?

Most sites are under 1 GB in space (really smaller than that, more like 100-200 MB). And they rarely use over 5 GB of bandwidth. There really is not any set formula or amount of visitors. It depends on how much data they transfer (i.e. how many pages they visit). If you have a site with 10 pages, each page is 100 kb. 15 people come on, theoretically that should be 15 MB roughly. However, each visitor goes to a different amount of pages. One may only see the first page, where another would see 4 pages, and another all of them. There really is no set amount.

However, the average usage for many of my customers is under 1GB of space and transfer.

Would that mean with the above numbers that if one person visited their site then they would use 100 MB towards the bandwidth quota? Not really, no. As Randy said, what matters is the activity of visitors.

Take one of my sites for example. About half of the visitors only view one page (sadly). They don't like what they read for some reason. :)

Also, caching may have a significant role in reducing bandwidth usage. If out of the 100KB that your average page has (I'm going with Randy's example), 50% are actually images that also appear on all your pages, most browsers will not download those images multiple times. They already have them stored in the cache, and call them from there.

A good formula I used in the past for clients is 1GB of bandwidth per 100MB of disk space. Using that formula I haven't had many customers go over their limit, however industry standards forced me to "revamp" the plans, because a year ago when I started it was hard to compete with companies offering a million terabytes of bandwidth for $3 a month. If you're looking for a good formula to use with clients, I would look at your current resources, then your competitors plans, and nestle somewhere comfortably in the middle. Keep in mind that overselling to a certain point is ok, as long as you have the means to meet it should you need to eventually.