For the last couple of years Google has provided a great tool as part of Google Labs called the Browser Size Tool. Unfortunately Google is “graduating” the tool from Labs and making it a feature of Analytics. By “feature” I mean a bit less useful than the existing tool. One of the best features of the tool is that you can enter any URL you want to evaluate and immediately see the page with the browser size overlay. (I’ve talked about this tool before and how you can use it to evaluate your on-page ad placement.) This was great for testing new designs before they went live to be sure that you could easily fit into the most common browsers. I might see if I can recreate the tool for my own private use, and until then I will rely on a Chrome extension that resizes my browser based on my selected test resolution.