WordTree’s KW Index Checker examines the indexing and ranks of all your Amazon keywords (Search Terms) in minutes, all for free. One click of a button discovers which keywords are not considered relevant by Amazon. The index checker is about 90% accurate since 10% of search terms Amazon treats differently and will show as not indexed when they really are. After confirming that the search term isn’t indexed try adding it to your subject matter field. Or try adding the search term to more than one location on your listing. This will usually get the search term to index. Some keywords are also blocked by Amazon’s system, such as big box brand names and some other random keywords – so if you run into a situation where no matter what you do you can’t index for a keyword – it might be blocked.