Other sellers' marketplace sales are almost an open book: analytics services estimate the revenue of any card, and part of the scouting is available with no tools at all. The question isn't access to the data but the ability to read it: half of seller mistakes come from blind faith in parsed numbers. Let's break down what you can learn, how much to trust it, and what to do with it.
Where competitor sales data comes from
Analytics services parse the public storefront: stock, prices, positions, reviews — and estimate sales from stock dynamics. Hence the key property of the data: these are estimates, not accounting. Accuracy drops on products with just-in-time restocking (stock gets replenished — "sales" get understated), on FBS with virtual stock, and when sellers play games with stock levels. Parsing conveys trends and orders of magnitude well; exact figures — no.
Which competitor metrics to watch
- Niche revenue and dynamics — the size of the pie and its trend: niche validation.
- Sales distribution in the top — monopoly or spread: the main indicator of whether you can break in.
- Price dynamics — who plays with price and how; the basis for answering dumping.
- Competitors' stock and out-of-stock — their stock gaps = your windows for capturing positions.
- Review accumulation speed — an indirect marker of real sales and promotion aggressiveness.
- Leaders' content and keywords — which queries they rank for, what their cards win with: CTR deep dive.
Free scouting without services
- Search results by hand: the top 30 for a key query — prices, reviews, content, badges. An hour of work, a picture of the niche.
- Competitors' reviews — a ready-made list of buyer pain points and weaknesses of rival products: raw material for your card.
- Buyer questions on leaders' cards — whatever confuses people will be explained on yours.
- Position dynamics of 2–3 competitors on 5 queries once a week — a notebook and discipline.
Services speed all of this up and add history — the platforms' paid analytics and external tools complement each other.
Typical reading mistakes
- Believing estimates as exact figures — compare orders of magnitude and trends, not rubles.
- Copying the leader head-on: they have a different cost base, review base, and budget — their strategy on your card will produce a different result.
- Ignoring the non-survivors: you see today's leaders, but not the dozens who went to zero on the same strategy.
- Scouting without your own economics: any "let's repeat what the competitor did" is first checked against your own unit economics.
Related deep dives: Repricer for marketplaces, Product positions on Ozon.
FAQ
"How can I find out a competitor's sales on a marketplace?" Analytics services estimate sales from stock and position dynamics. These are estimates: trends and orders of magnitude are reliable, exact figures are not. For decision-making, that's enough.
"Which analytics service should I choose?" Any mature service covers the basic tasks; what matters more is what exactly you look at and what decisions you make. Start with the free tiers of a few services and your own checklist of questions.
"Can I analyze competitors for free?" Yes: manual analysis of search results, competitors' reviews and questions, tracking positions and out-of-stock. Slower than a service, but enough for one niche.
"How accurate is competitor sales data?" As accurate as estimates from indirect data can be: decent on stable FBO products, noticeably worse on FBS and when sellers play with stock. Cross-check conclusions with a second source: reviews, positions, price dynamics.
