An Issue Of Width:

The Resolution Problem

There is a problem that has plagued us ever since graphical designs for web pages began, and yet it's never been solved.

The computer landscape is littered with monitors, from 12 inch laptops to huge 30 inch desktop units. Different sized monitors can handle different page widths.

Why is this such a problem? Well, let me explain.

What is Resolution?

Before we get to the problem, you need to understand what a screen resolution is. To put it simply, your resolution is the number of pixels that can be displayed across your monitor, horizontally and vertically. For example, at 640x480 resolution (the lowest anyone still uses), your screen is 640 pixels wide by 480 pixels high.

Most monitors can handle more than 1 resolution, and will give you a choice between them. Typically, there will be a lower resolution that fits less pixels on the screen, but makes them look bigger, and a higher resolution that displays more pixels, but makes everything look small. The default is usually somewhere in the middle.

To check the resolution you're using now, right click on your desktop and choose Properties. Click the Settings tab and look at the screen resolution section. On most computers, there will be up to 4 settings to choose from: 640x480, 800x600, 1024x768 and 1280x1024.

If you change your resolution and go to some web pages, you will quickly get an idea of how much width each setting gives you.

The maximum width that you can safely design your website for, in pixels, will be the lowest width you expect your visitors to be using. In almost all cases, this is 800x600.

640x480 users are now a small enough minority that you can ignore, as they'll be used to sites displaying incorrectly. At 800x600 and up, though, you should test your site to make sure it looks right.

The Price of Failure

If you don't test your site correctly, then various things will go wrong. At resolutions lower than what you designed the site for, visitors may see horizontal scrollbars. If you fix the site's width too low, though, visitors using higher resolutions may just see a thin strip of your website in the middle of their screen.

Possible Solutions

The most popular solution to the resolution problem is to just design as if everyone was using 800x600 -- after all, people with big monitors can just make their browser windows smaller. To make a fixed width design, simply set the CSS width of your body tag to the width you want in pixels (ie. 800px).

If you take this approach, you will probably want to set the CSS margins to auto, as this will put your fixed-width page in the centre of larger screens -- if you leave the margins alone, then your page will appear on the far left of the web browser at high resolutions, which is common to see but still looks bad.

The more complicated, but technically better, way of doing things is to make sure that your design will work well no matter how wide the browser is, because it stretches to fit. These kinds of designs are known as 'elastic'. This can be difficult, but it's doable, especially for relatively simple designs. If your design has 3 columns, for example, you can make the left and right columns fixed-width but leave the middle column to take up all the remaining width.

The biggest concern with elastic designs tends to be the graphics: if you have a fixed-width header, how can you adjust your site for any possible width? In most cases, the solution is to make your header an image that floats over a background continuing it.

For example, you might use an image of navigation text floating over a line -- you can then continue that line as the background image, to avoid it suddenly appearing to stop if the viewer's resolution is wider than your navigation images. CSS gives you a lot of power to create illusions like this: make good use of it.