IE7 RC1 vs. Firefox2 RC1

Internet Explorer version 7 RC1 and Firefox version 2 RC1 are now out so I thought it would be a good time to do some simple side-by-side comparisons. The "RC" stands for Release Candidate, meaning that these are the near-final versions.

Unfortunately IE7 wouldn't install on my primary computer so I had to compare them on a slower laptop.Firefox 2 appears to have a slight but unmistakable edge It's an IBM Thinkpad T42 with a 1.7Ghz Pentium M processor and 2GB of memory, running Windows XP SP2.

First I tried the (in)famous Acid2 test, a page "written to help browser vendors ensure proper support for web standards". Here's the output drawn by IE7RC1:

And here's the output drawn by FF2RC1:

Neither one gets it quite right but Firefox looks closer. If you want to see what these are supposed to look like, click here.

Advantage: Firefox 2 

Next I ran a test from scragz.com that simply measures how long it takes the browser to render a large (>800K) table. Times varied considerably (from 4.186 to 5.788 seconds) so I ran the test 5 times and averaged the lowest 3. The results:

• IE7RC1:  4.346 seconds
• F2RC1:   4.289 seconds 

Given the variability of the times we'll call that a statistical tie.

Advantage: None 

JavaScript performance is especially important for today's Ajax applications. So for the final test I ran the JavaScript Speed Test at 24fun.com. This measures 7 aspects of the browser's JavaScript engine. I ran the test 3 times and took the average for each of the 7 tests (all times in seconds):

1. IE: 1.002, FF: 1.642 (Counting to 10000)
   
2. IE: 4.743, FF: 2.086 (Open pop-ups)
   
3. IE: 0.497, FF: 0.554 (Replace images)
   
4. IE: 1.325, FF: 0.691 (Text manipulations)
5. IE: 1.195, FF: 0.183 (Set tables)
   
6. IE: 1.445, FF: 1.946 (Put layers into place)
   
7. IE: 1.786, FF: 0.921 (Calculate x-mas)
   

Total: IE: 11.993, FF: 8.024

Advantage: Firefox 2

In conclusion, picking a browser involves more than just running a few benchmarks and going with the fastest one. Your decision will be influenced by many factors such as security, compatibility with the sites you use, support for your platform, and extras like bookmarks and web feeds. All we can say for sure is that on this computer, for these tests, Firefox 2 appears to have a slight but unmistakable edge over its closed source rival from Redmond.

I didn't look at other contenders like Opera and Safari here. But regardless of which browser you use, you are the real winner in this battle as the browser superpowers try to outdo one another.