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Acid2 Browser Test

Acid2 is a test page, written to help browser vendors ensure proper support for web standards in their products. Please take the Acid2 test!

If you’d like more in-depth information about the Acid2 test, we’ve provided a detailed technical guide that explains how the test works.

Note: Some 827 people (rough estimate, contents may have settled during shipping) have written to point out that the CSS used in the test is invalid. This is deliberate, as a means of exposing the ability of user agents to handle invalid CSS properly.

Note: When taking the test, you should use the default settings of the browser you are testing. Changing the zoom level, minimum font size, applying a fit-to-width algorithm, or making other changes may alter the rendition of the Acid2 page without this constituting a failure in compliance. (Added 21 July 2006)

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Recent Task Force Buzz

Acid 2 Test Back to Normal

By Derek Featherstone | July 24th, 2008

The Acid 2 test hosted here on the WaSP site was broken but is now fixed.

For a while now we’ve had a problem with the Acid 2 Test on the WaSP site. If you’re unfamiliar with the Acid 2 Test, it is essentially a test for browser vendors to use as a means to gauge their standards compliance. If your browser renders the Acid 2 Test page the same as the Acid 2 reference rendering, then you know you’re hitting the mark.

I’ll be honest: over the last 10 days, I’ve learned more about the Acid 2 Test than I ever wanted to know. If you want to do the same, you might start with Acid 2: The Guided Tour.

The short version is that part of Acid 2 is a test for the way a browser handles an <object> element when the data attribute references a URL that returns an HTTP status code of 404. A number of caching rules, mod_rewrite rules and redirects all collided to create a problem with our 404. The cached version of our 404 page was returning an HTTP status of 200. As you might expect, this basically makes the test useless.

Acid 2 was broken. Now it is not. Carry on.

More Buzz articles

Title Date
What’s the best test for Acid3? January 16th, 2008
IE8 passes Acid2 test December 19th, 2007
Safari 3 Public Beta for Mac and Windows June 12th, 2007
Acid2 and Opera 9 Clarifications: Yes, Opera 9 Passes the Test July 20th, 2006

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All of the entries posted in WaSP Buzz express the opinions of their individual authors. They do not necessarily reflect the plans or positions of the Web Standards Project as a group.

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