Want to know if the sales rank of your product is good?
FBA Toolkit is a FREE Website site that shows an interactive chart of every Amazon category. Just place your cursor along the line and it shows the sales rank and how many items will sell per day at that rank.
Personally, my goal is to always be in the top ten percent of any category sales rank. You used to be able to determine that by pulling down a category in the Amazon search box and type in two brackets. But Amazon no longer does this, so the FREE FBA Toolkit is the only way I know of now to get this information.
This tool is also a very helpful Free Tool for Amazon Affiliate Partners