Phil VK7JJ has put together a website that offers a very useful way to visualize the performance of transmitting and receiving WSPR stations.
Inputting a callsign and clicking on 'Search WSPRnet' results in various charts and textual data displaying overall SNR ratio, kilometers per watt, frequency vs. distance and other data.
While the charts are useful for single band operations, they become quite a bit more interesting if the station being analyzed is operating on two or more bands, particularly around sunrise and sunset as the lower bands begin to exceed 20m and higher bands in terms of the distance of receiving stations.
I believe similar data is offered by DXplorer for a fee. But here the data is provided without a price tag: