Browser compatibility is one of the trickiest issues in web site design. Just because a site looks great in Firefox (which is apparently programmer-friendly) or IE7 doesn’t mean that it works well (or even at all) in IE6 or IE8. As for Safari, Chrome, Mozilla and Sea Monkey (!), you have to decide whether the number of visitors requires compatibility testing.

You would think that blanket compatibility, at least of the major browsers,  would be top of every web designers list of “Must Haves”. Sadly, I found this isn’t always the case — it’s something that needs to be written into the contract and then tested, tested and tested again.

Last year I worked on a Website for a client where the site looked great in Firefox and IE7. The problem was that they used IE6 in their office and in that browser, they couldn’t see the entire page so important information appeared to be left off. The programmer’s initial response? They need to upgrade their browser. I think not!

This year I had a client who had a Website that worked perfectly in everything except IE7. If it was an obscure browser like Sea Monkey, maybe it wouldn’t be an issue but according to my own tracking, IE7 is still the most popular browser on the market. The programmer’s response? We’ll fix it in the next phase. I think not! Browser compatibility is integral to the success of your clients’ websites. It’s not something you get to later. I understand that each version of Internet Explorer has specific programming requirements, but absolute conformance just needs to be part of the completed job.

Who uses what browser depends a lot on your target audience. Consumers tend to upgrade their browsers frequently than large corporations, where IT departments generally standardize the use of a particular browser company wide.  I know several companies that still use IE6 (with no immediate plans to upgrade) even though IE8 is gaining market share.

While there are mass statistics that dictate browser share, I monitor the visitors on my own and my clients’ sites to give me a finger on the pulse of the industries that I serve. I’ve found that my figures are not much of the mark as those reported in Wikipedia.

For example, here are the trends I’ve seen over the past year for one of my clients, which is in the telecommunications industry. The people viewing their site are fairly technical, international in scope, and many work for larger companies.

Here are the stats for visitors to their site during the past 30 days:

This chart shows browser share over the past 30 days. IE is by far the most dominant browser. More than 63% use IE with Firefox at just under 30%.

This graph shows the breakdown of the different IE Versions. No surprise -- IE7 is the predominant browser with 48.5%, but IE6 still enjoys heavy usage for an "old" browser at 33%, and IE8 adoption is up to 18%, a significant increase since the beginning of the year.

Look at the stats from Jan '09. Just six months ago, fewer than 2% of our visitors were using IE8. Interestingly, IE6 usage is pretty consistent; IE7 had a larger share of the browser market.

So, what’s the bottom line? Don’t underestimate the longevity of the major browser versions. Make sure that your clients’ websites work on all of them. Browser testing should be done by your web designer or firm, but it’s a good idea to check for yourself. I generally have the current versions of Firefox and IE on my computer but there are resources on-line that can help you look at some of the versions not immediately available.

Here are two that I’ve used:

Browsershots.org lets you look at your website in a large number of platforms (some of which I’ve never heard of!) You can look at a limited number of screen shots for free.

Browsercam.com lets you see your website using any browser and any operating system.