Sales Estimator

Best Seller Rank is the one demand signal Amazon shows publicly. It is not a sales number, but it can be read into a sales range. This skill turns a BSR into an estimate, and a set of BSRs into a market size, with honest confidence bounds.

When to use this

• Estimating how many units a product or competitor sells per month.
• Sizing a niche from the BSRs of its top listings.
• Judging whether demand justifies entering a category.
• Comparing the demand behind two products or two price points.

The framework. How to read a BSR

BSR is a rank, not a count, and the rank-to-sales curve has three properties that must shape every estimate.