Back in November, Google changed the default user interface for image searches. In doing so, they hid the ability to filter image search results by specific sizes. While the result of this change is a simpler search experience, it's now harder for users -- like art teachers who like to flex their "fair use" powers and give lectures with high-resolution images -- to quickly find the desired image size in their favorite search engine.
Luckily, the image size filter functionality still exists and searchers can use it by scrolling to the bottom of the default image search view and clicking a link at the very bottom called "Switch to basic version."
Here's what it looks like:
For super-sophisticated power users, there's still the ability to tell Google exactly what size you want by adding the following code with the appropriate dimensions to the end of an image search:
SECRET URL CODE: &tbs=islt:2mp,isz:ex,iszw:1920,iszh:1080
In this example, we're telling Google to find us images with dimensions in the 1920x1080 pixel range. Once this extra code is used, a wider range of sizing options becomes available. Alternatively, you can also click the "search tools" button.
Here's what the Google image search interface looks like once the extra code is added:
Google is constantly testing out new interfaces to speed up the search experience for users. The changes to image search are supposed to aid in that; i.e., fewer options are faster. So, while I hope this information will be accurate forever; don't be surprised if I'm back later with an update for one of Google's updates.