Originally Posted by chitownflyer

Go to united.com and select the planning travel tab. Then select full flight search and sign in with expert mode. If you do not see this, you can select expert mode from your display preferences.

On a three cabin plane, Business will show up as C, D, and Z classes. All the Economy fare classes are Y, M, B, H, Q, V, W, S, T, K, and L. This will show you how many seats they are selling in a particular class.