Organic Rank
Also known as: Search Ranking, Keyword Ranking
Organic rank is where a listing appears in Amazon's unpaid search results for a given keyword, driven primarily by sales velocity and conversion on that term.
Organic rank is your listing's position in the natural (non-sponsored) search results for a specific keyword. Because the first page captures the overwhelming majority of clicks, ranking on page one for high-volume terms is the difference between strong free traffic and obscurity.
Amazon's ranking algorithm (often called A9/A10) weighs relevance — is the keyword indexed in your title/bullets/backend — and performance: sales velocity and conversion rate for that keyword, plus review count/rating, price, in-stock rate, and Prime eligibility. A listing that converts a keyword's traffic into sales climbs that keyword's organic rank, which brings more traffic, a compounding loop.
Organic rank is distinct from BSR: BSR ranks units sold within a whole category, while organic rank is per-keyword position in search. Sellers buy Sponsored Products traffic partly to seed early sales velocity on target keywords and bootstrap organic rank during a launch.
A new listing sits on page 4 for "yoga mat." After a launch period of Sponsored Products ads driving sales and a 13% conversion rate on the term, it climbs to position 8 on page 1 and starts receiving steady organic traffic.