How I determine how much bandwidth I will need?

I have not made my decision yet as to which webpage provider I will use. There are many aspects to consider! One that I am not very familiar with is bandwidth. I understand the concept but do not know how to measure it.

I will give you 4 examples of things that I plan to regularly do on my website. The numbers I have chosen are probably not realistic but were chose to illustrate the concept and make math simple:

1. Host streaming video. For example if a video file on the server is 2 mb and 5 people watch it in one day does that equal 10 mb of bandwidth? If 5 people watch it at the same time is that only 2 mb of bandwidth?

2. I want people to be able to watch my beautiful aquarium 24/7 via my webcam. If it transfers 1,000 kb of data per hour does that equal 24,000 kb of bandwidth per day?

3. If I have a file that is 10 kb on my site and 10 people download it every day is that 100 kb of bandwidth?

4. Forum rooms - I don't have the slightest idea how much bandwidth forums take. If 10 people chat for one hour how much bandwidth does that usually take up?

Please feel free to refer me to tutorials if you like.

a bit of an add but it should give u the general idea

If 5 people watch a streaming video it will still be 10 mb total bandwidth as the information has to be sent to each user individually.

That's right. But if 300 people watch it for 10 minutes in one day, then that's 50 hours total, which is 50,000 kb.

Yes!

Don't confuse chat with forums. Webforumz is a forum. The amount of bandwidth used depends entirely on how many users are using the system, how long for, what they do, etc.

Here's an example from this site. Last week we had 12,381 sessions (1,768.71 daily), 63,333 pageviews (9,047.57 daily) which equates to 1.42 GB (207.31 MB daily).