What is a good width for a website?

There are a number of acceptable sizes, but I would recommend 960px. I read an article that recommended it, I'll try and find that. You can look at sites you like and respect and see what they use. I'd definitely check out alistapart.com, they're a great source for articles about best of breed accessibility and standards in web design, and think they also use 960px. (Fluther does as well).

It also depends on your target audience and the type of website... is it a blog with primarily text content? Showing video? Tons of pictures? I think the rule of thumb is to make it as narrow as you can without sacrificing the layout of your content.

Here's that article on optimum screen width Ben mentioned: www.cameronmoll.com/archives/001220.html

960 px wide (like this website) is not only a comfortable width for most screens (1024 px wide and up), but the number also has many common denominators, making it easy to design on a grid as explained here: www.cameronmoll.com/archives/2006/12/gridding_the_960
Both of these articles have very informative comments as well. Worth reading.

Sweet. I had figured out fluther was 960 but didn't know if that was standard or not. Thanks guys!

I would agree for the most part with mark and ben, though i'll add a small note. I know it may seem nit-picky, but i usually prefer around 900px. :) also the comment about audiences is particularly relevant if there is a chance that people viewing your site might have really really old equipment (like under funded schools, less well off people with hand-me-down computers, people who refuse to ever upgrade for personal reasons, or people in foreign countries where conditions aren't as good, etc) - so just keep in mind what the site's for, i guess.
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...also, be sure to consider whether it's a centered page, or a left-anchored page, or what, because that can also affect how you design your width.

i always make sure my sites look good at 800 x 600. i just watch the way my wife uses her ibook... it's got a 1024 px wide screen, and she keeps her web browser window around 800 px wide.

Well I think for now I will use the 960. This project is only for 20 users or so...worse case I can conduct a poll and find out what size is good.

if you personally know your entire intended audience, it's absolutely worth it to run a little email poll and get it right form the start.

I believe if all you want to do is avoid horizontal scrollbars when the browser window is maximized, you can get away with about 990px across. That's close to analogous to the standard 768px width to accommodate browser chrome on 800x600 monitors.

It depends on the project & audience in question. Even if you know that 100% of your audience is using 30" cinema displays, it is usually best to try and use only as much space (and whitespace) as needed to completely convey the concepts supporting the subject matter.

Don't forget about elastic layouts. The web was initially designed as a means to get info across any platform, regardless of screen size. Keep that in mind, and your site will determine its own 'dimensions'.

A recent study found that the most common width for the most popular websites around the world is about 900px.

Here’s the study in case you’re interested: http://www.dostuffright.com/CSS-font-styles-color-margin-padding-a-inline-code