In what browsers do you test your websites?
- Google Chrome / Iron Browser
- Internet Explorer 10 (with Compatibility mode)
If it is a local web application software for client means i only test clients main browser and any common one other browser.
if it is a public website or application i check in all major browsers and support for maximum versions also like from IE6 to IE9
I usually test in Firefox, IE8, Chrome, Safari and Opera on PC and Mac. For other versions of browsers I use browsershots.org/, which provides screenshots of the site in different browsers. It's not ideal since you can't test everything on the site (Browser Shots just provides images), but it's far less time-consuming than going through every possible browser/OS combination.
My boss uses Opera so I have to test in it too! He actually found a jQuery issue that happens only in this browser.
I tend to just follow A-grade supported browser from Yahoo! for testing. Though I no longer spend much time fixing anything minor on IE6.
Graded Browser Support
My list of browsers that I test is substantially the same as many of the answers here, but none of these really tell you which you should test.
You should examine your logs or other web analytics data to see which browsers your users are using. My sites' users are generally non-technical -- we have higher than average use of IE6 (sigh) but virtually no visits from Opera. A Mac news site like Daring Fireball is disproportionately Mac/Safari and probably has single digit percentage for all IE versions combined.
Look at the aggregate numbers. Test for the browser versions which combine for at least 99% of your traffic.
A couple more notes:
If you get Mac traffic, test on a Mac. Don't assume that Safari, Firefox and Chrome will render the same on Windows. The same goes for Linux.
Even if the CEO or some other important person is the only one viewing your site on a Blackberry, then you might consider testing that as well.
Mac OS X:
Sunrise (2 versions)
Maybe its overkill, but I tend to follow the BBC's browser supports standards (this also looks good when talking to clients), whilst remembering Andy Clarke's words:
"If you’re one of those people who is hiding behind the outdated notion that web sites should look, or be experienced, exactly the same in every browser, you are in for a nasty shock."
I use IE collection on a virtualBox (from a mac).
Some sites i test up to (down to) IE6, but most sites i check (and hack and pinch the bugs out of them, the most i could) in IE7 and up.
I test regularly in Firefox, IE8 + compatibility mode, Opera & Chrome.
Safari uses the same rendering engine (WebKit) as Chrome, so the results will be pretty much the same as those of Chrome. I tested that a few times and the results were as expected, so I dropped Safari from my testing loop.
That covers 99% of my total visitors anyway. I can live with 1% having potentially a less than optimal browsing experience.
Every once in a while I test on other computers. Typically, I drop by a cybercafe or two after a major change, and see what it looks like on other hardware configurations.
My opinion is that trying to get that last 1 percent covered is not a good investment of my time, and probably isn't a good investment for most webmasters. That one percent will take a disproportionate amount of work that would be better invested in improving my site for most of my customers, the other 99%.
I test IE6 - 8 and Opera, Safari, Chrome and firefox.
I only test the latest version of Safari, Chrome, and Opera because I have noticed that people who use these browsers tend to keep them updated. I check the last 2-3 versions of FireFox.
I currently testing my websites in this browsers. I have this browsers installed through virtual machines.
Internet Explorer 6 on XP
Internet Explorer 7 on XP
Internet Explorer 8 on Window 7
Firefox 1.5 on XP
Firefox 2 on XP
Firefox 3 on Windows 7
For IE testing, I use IETester and IE8, both regular and in compatibility mode. The other major browsers have a much quicker release cycle, so I find it's not as important to test their older versions.
I have Firefox 3, Internet Explorer 8, Safari, and Opera on my desktop for testing because they are popular (I only use Firefox for normal Internet activites), and a browser testing service such as browsershots.org for a greater selection for testing the final website (I use the default recommended browsers).