What is BSR (Best Seller Rank)?
Amazon Best Seller Rank (BSR) is a number assigned to every product in Amazon’s catalog that indicates how well it’s currently selling relative to all other products in the same category. A BSR of #1 means the product is selling more units than any other product in its category. BSR is updated hourly based on recent sales velocity.
Why It Matters
BSR is the primary visible signal of a product’s sales performance. It is used by buyers to assess popularity and social proof (‘bestseller’ badges appear on low BSR products), by competitors to gauge market demand and competition, and by sellers to track their own sales velocity and campaign performance. BSR fluctuations provide real-time feedback on whether a pricing change, new listing content, or PPC campaign is driving results.
How It Works
BSR is calculated based on recent sales velocity with heavier weighting given to very recent sales over historical sales. This means BSR responds quickly to sudden spikes in sales (during a Prime Day promotion, for example) but also drops quickly after sales normalize. A product can rank in multiple categories simultaneously — its main category BSR and sub-category BSR. Amazon’s #1 Best Seller badge appears on products holding the top BSR in their sub-category.
Real-World Example
A seller’s bamboo kitchen utensil set has a BSR of #3,250 in the Kitchen & Dining category and #12 in Bamboo Kitchen Utensil Sets. The sub-category BSR of #12 earns the Amazon Best Seller badge, which appears on the product page and in search results — significantly improving click-through rates and social proof.

