Robert McLaws: Windows Edition

Blogging about Windows since before Vista became a bad word

IE8 Passes Acid2, Finally Achieves Full Standards Compliance

"Don't misinterpret silence for inaction."

That's what Dean Hachamovitch, GM of the IE Team, said in a blog post two weeks ago. Boy, he wasn't kidding.

At first glance, this test seems simple. I think it actually offers a view into the subtle and complex world of web standards in a number of ways. Showing the Acid2 page correctly is a good indication of being standards compliant, but Acid2 itself isn’t a web standard or a web standards compliance test. The publisher of the test, the Web Standards Project, is an advocacy group, not a web standards defining body.


The key goal (for the Web Standards Project as well as many other groups and individuals) is interoperability. As a developer, I’d prefer to not have to write the same site multiple times for different browsers. Standards are a (critical!) means to this end, and we focus on the standards that will help actual, real-world interoperability the most. As a consumer and a developer, I expect stuff to just work, and I also expect backwards compatibility. When I get a new version of my current browser, I expect all the sites that worked before will still work.


Now, with all that context, I’m delighted to tell you that on Wednesday, December 12, Internet Explorer correctly rendered the Acid2 page in IE8 standards mode. While supporting the features tested in Acid2 is important for many reasons, it is just one of several milestones for the interoperability, standards compliance, and backwards compatibility that we’re committed to for this release. We will blog more on these topics. Here’s a relevant video.

This is great news, not just for developers and web purists, but also for Microsoft, who may have just satisfied a key request of the recent Opera antitrust lawsuit. It will be interesting to see what else is in IE8, which I'm assuming we'll hear more about at MIX '08.

Posted on Dec 19 2007, 12:51 PM by Robert McLaws
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  • There is an interesting post over at

    December 19, 2007 3:30 PM
  • Ben Hollis said:

    You know that passing Acid2 doesn't mean that IE8 has achieved "full standards compliance", right? Not that that phrase has any meaning...

    December 20, 2007 12:30 AM
  • Eric Wilson said:

    I'm always confused why people think the ACID2 test is the definition of full compliance with web standards (or even why they ding Microsoft for not implementing it and then say nothing about the fact that Firefox doesn't render it either).

    1) The ACID2 test takes some assumptions from CSS 2.1, which is not even a fully approved standard.

    2) ACID2 tests a small subset of CSS

    3) Since when does CSS == all web standards anyways?

    December 20, 2007 12:00 PM