Acid3 Test is a group of browser compitability tests. Acid3 test is a good indicator on how Web ready is your browser.
Acidtest is part of the web standards project. Latest Firefox 9.0.1 passes the test on 100% (100/100).
I've tried it with Epiphany and it scored only 67/100, still I'm using Epiphany on daily basis and I'm quite happy with it.
The tests involved are testing browser for:
- Checks on HTML tables and forms browser rendering
- SVG compitability testing
- DOM1 and DOM2 compitability
- Unicode (UTF-16 and UTF-8) browser compitability
- XHML, SMIL, CSS, HTML compitability
- Content-type image/png, text plain etc.
Each of the test is represented visually by a rectangle. If the a test stage is passed you see a new rectangle appearing in the tested browser.
In wikipedia, there is a thorough list with web browsers by type and engine and the level of support for the Acid3 test.
The test is of great use if you're web developer.