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Which ASINs moved your Amazon sales, and why.
Download Detail Page Sales and Traffic by Child Item twice, once for each period, and paste both below. You get the products that lost and gained the most, each change split into sessions, conversion and price, and a flag wherever the Buy Box fell. The files are read in your browser and never uploaded.
Example reports for 8 made-up products, September 2025 against September 2026. Replace them with your own, or .
In Seller Central: Reports, Business Reports, then Detail Page Sales and Traffic by Child Item. Set the dates, download the CSV, then do it again for the other period. The Business Reports guide shows where each column comes from.
Which products moved
Lost the most
Gained the most
How each change is split
An ASIN's sales are its sessions times its unit session percentage (units over sessions) times its average selling price (sales over units). The change between the 2 periods is split between those 3 by each one's share of the change, so the parts add up to the whole. That says which of the 3 to look into first, and the check under each ASIN lists where to start.
The Buy Box flag shows when an ASIN's Featured Offer (Buy Box) Percentage fell 5 points or more. When it does, check stock and other sellers' offers on that ASIN before changing the listing.
Left out. Refunds, fees and ad spend, so this is ordered sales, not profit. Compare periods of the same length, and the same season where you can, or the calendar does the moving. Parent ASINs aren't added up, so a product with variations shows once per child.
Amazon is one channel. We read all of them
If Shopify, Walmart or wholesale went the other way, an Amazon drop can be buyers moving, not demand leaving. The free monthly business review puts the channels side by side. The free report goes further: every channel, each likely cause tested against your data, and the actions ranked with an owner and a date. Your first monthly review is free, and the free month ends on its own.