What Is Terapeak? eBay's Free Research Tool Explained (2026)

A reseller finds twelve boxes of wireless earbuds at a price that looks too good to walk away from. The listing part is easy. The part that decides whether this was a good afternoon or an expensive one is different: is anyone on eBay actually buying these, how much are they paying, and how many other sellers are already sitting on the same stock? Terapeak is the tool eBay built to answer that, it lives inside Seller Hub, and for the core research features it costs nothing.

Quick answer: Terapeak is eBay's own market research tool, now labeled Product Research inside Seller Hub. It gives you access to the last three years of real eBay sales data — sold prices, price ranges, shipping norms, seller counts and demand trends — free to any seller with Seller Hub access. A second tool, Sourcing Insights, comes with a Basic Store subscription or above.

• Free: Terapeak Product Research costs nothing for sellers with Seller Hub access.
• Real sold data: actual prices paid, including accepted Best Offers — not asking prices.
• Three years deep: with one important exception covered below that trips up most sellers.
• Research only: it tells you what sold. It does not source the product, price it against a supplier, or list it.

Jump to a section:

• What Terapeak is in 2026
• Terapeak's two tools, and who pays for which
• How far back the data goes — and the 90-day exception
• What Terapeak will not tell you
• From a Terapeak verdict to live, monitored listings
• Terapeak FAQ

What Terapeak Is in 2026

Terapeak started life outside eBay. It was an independent commerce analytics company that sold subscription access to marketplace sales data, and for years sellers paid a monthly fee for it on a separate website. eBay acquired the company in 2017, spent the following years rebuilding its data backend on eBay's own stack, and folded the features directly into Seller Hub. The standalone product went away. The name mostly went with it.

Today the tool is labeled Product Research in the Seller Hub navigation, under the Research tab. Sellers who have been on the platform for a while still call it Terapeak, search for it as Terapeak, and talk about it as Terapeak in forums, which is why the old name refuses to die even though eBay stopped printing it on the button. Both names point at the same thing.

What it actually does is narrow. You search a keyword, a UPC, an MPN, an ISBN, an EAN or an eBay product ID, filter the results, and eBay returns aggregated statistics drawn from completed transactions on its own marketplace: average sold price, the low-to-high sold price range, average shipping paid, the share of listings offering free shipping, total units sold, total revenue, how many distinct sellers moved the item, which listing format they used, and how the trend line moved over the period you chose. eBay documents the full metric set on its Product research help page.

The important structural point: this is first-party data. It is not a scrape and not an estimate. When Terapeak says an item sold for $43.50, a buyer paid $43.50, and that includes cases where the seller accepted a Best Offer below the listed price — a number the ordinary sold-listings search hides behind a strikethrough. That is the single biggest reason to open Terapeak instead of eyeballing sold listings, and it is why the tool holds up even against paid research platforms. Sellers weighing paid options usually end up comparing them against this free baseline; we ran that exercise across six tools in our breakdown of the best Terapeak alternatives for eBay product research.

If you want the click-by-click version — which filters to set, in what order, and how to read the output screen — that is covered separately in our Terapeak product research workflow guide. This article stays on the higher-level question of what the tool is, what it covers, and where its edges are.

Terapeak's Two Tools, and Who Pays for Which

Most confusion about Terapeak pricing comes from the fact that "Terapeak" is now two separate tools with two different access rules. Sellers read that Terapeak is free, log in, find one of the two missing, and assume something is broken.

Tool	What it analyzes	Who can access it	Best used for
Product Research	Individual products and search terms	Any seller with Seller Hub access, at no cost	Validating a specific item before you buy or list it
Sourcing Insights	Whole eBay categories	Business sellers with a Basic Store subscription or above	Deciding which category to move into next

Product Research answers item-level questions. Should I buy this pallet of earbuds? What do they sell for used versus new? Is demand rising or falling? Sourcing Insights answers a different question entirely: which corners of eBay have buyers searching hard and relatively few sellers listing? It reports category search volume, active listing counts, the search-to-listing ratio, click-through rate over a year, and the listings eBay flags as top opportunities.

The practical split is this. Nearly every day-to-day sourcing decision runs through Product Research, which costs nothing. Sourcing Insights matters when you are choosing a niche rather than an item — and since it rides along with a Store subscription you may already pay for, the real question is not whether it is worth buying but whether you already have it. eBay lists current Store tiers and what each includes on its Store subscription help page.

How Far Back Terapeak Data Goes — and the 90-Day Exception

Ask five seller guides how much history Terapeak holds and you get three different answers. Some still say 365 days. Some say two years. eBay's own documentation says the last three years of sales data, with date ranges selectable from a single day up to the full three-year span.

Three years is correct. But there is a caveat inside eBay's own metric list that almost nobody carries forward, and it quietly breaks the most popular way sellers use the tool. Sell-through rate — the units-sold-against-units-listed ratio that every sourcing guide calls the number that matters — is calculated only for searches covering items sold 90 days ago or less. Pull a two-year window to check whether an item has durable demand and the sell-through figure you were counting on will not be there to read.

Sellers hit this constantly and read it as a bug or an account problem. It is neither. It is a documented limit of the metric, and the fix is to stop treating Terapeak as one search and start treating it as two.

1. Run the 90-day window first. This is your competition read. Sell-through rate, total sellers and current sold price range all populate here. If sell-through is thin and the seller count is high, the item is saturated and nothing in the longer window will rescue it.
2. Then run the same search across one to three years. This is your stability read. You are not looking for sell-through here; you are looking at whether the average sold price holds steady or slides, and whether the trend line has a seasonal peak you would be buying into or out of.
3. Compare the two. Healthy demand looks like a workable 90-day sell-through and a price line that has not been eroding for two years. Strong recent sales on a long, steady decline usually means you are catching the tail of something.

That two-pass habit costs an extra thirty seconds and separates a genuine winner from an item that merely had a good quarter. It is also the difference between the seller who sources against last week's noise and the one who can tell a seasonal spike from a real market, which is exactly the judgment behind our category-level look at what actually sells most on eBay.

One more thing worth knowing while you are in there: the sold titles in your results are a keyword source, not just a price source. The titles attached to the highest-selling listings show you the exact terms buyers converted on, and those terms feed straight into how eBay's search engine matches your listing — the mechanics of which we cover in our explainer on how eBay's Cassini search engine ranks listings.

What Terapeak Will Not Tell You

Terapeak is a demand instrument. It measures one side of the trade with real precision and is completely silent on the other three, and every gap below is where sourcing decisions actually go wrong.

It does not know your cost. Terapeak reports the price a buyer paid. It has no view of what you would pay a supplier, so the number it hands you is revenue, never margin. A category can show a healthy average sold price and still be unsellable once supplier cost, shipping and eBay's fees come out. eBay publishes its current fee structure — a percentage final value fee that varies by category, plus a fixed per-order amount — on its selling fees page, and those need to be in your arithmetic before a product looks viable. We work through the full calculation in our guide to eBay dropshipping profit margins.

It does not know whether you can get the product. A validated winner you cannot source reliably is a research result, not a business. This is the gap Ecomli closes. Ecomli is an AI-powered automation platform for eBay sellers that handles sourcing, listing, pricing and fulfillment in one place, and its Smart Scraper attacks this exact problem: it scrapes competitor eBay stores and pulls out the products that have already sold, with the matching supplier attached, ready to import in a few clicks. Instead of validating an item in Terapeak and then hunting for someone who can supply it, you start from proven sellers whose supply chain is already wired up.

It does not watch anything after you list. Terapeak gives you a snapshot on the day you search. Supplier prices move, stock runs out, and a listing that was profitable in March quietly becomes a loss-maker or an order you cannot fulfill. Ecomli's stock and price monitoring runs against your suppliers continuously and updates the listing on its own — repricing when supplier cost moves, pausing when stock disappears — so the margin you researched is the margin you keep. Sellers who want to see how that plays out against a fixed floor can read our breakdown of repricing that defends your margin floor.

It does not do the work. Research produces a shortlist. Turning a shortlist into a store means writing titles, building listings, placing supplier orders, and updating tracking — the part that eats the week. That execution layer is a separate category of tooling entirely, and comparing the options is a job of its own; our ResellKit review is one example of how those tools stack up on listing throughput. You can see how Ecomli approaches the same workload on our automation overview.

From a Terapeak Verdict to Live, Monitored Listings

The reason a free research tool has not made eBay easy is that research was never the bottleneck. Deciding an item is worth selling takes a few minutes. Getting a hundred of those items listed, priced against a live supplier feed, and fulfilled without you sitting at a keyboard is where stores stall out.

Ecomli is built for that half of the job. Smart Scraper handles the sourcing side, scraping entire Amazon and AliExpress catalogs, or competitor eBay stores, into import-ready products with suppliers attached. Continuous monitoring keeps every listing honest against supplier price and stock changes. Auto-ordering places the supplier order when a sale comes in and pushes tracking back to the buyer, so the loop from sale to delivery closes without manual purchasing. And because the same catalog can go out to Amazon and Etsy as well as eBay, a store built this way earns across several marketplaces rather than living or dying by one.

Terapeak stays useful in that setup. Use it to sanity-check what the scraper surfaces, to confirm a price band before you set your margin rules, and to read seasonality before you commit slots to a category. What changes is that the verdict turns into live listings the same afternoon instead of sitting in a spreadsheet. Plans and listing limits are on the Ecomli pricing page.

Terapeak FAQ

Why is my Terapeak sell-through rate blank?

Almost always because the date range is too long. eBay calculates sell-through rate only for searches covering items sold within the last 90 days. If you set a one-year or three-year window, the other metrics populate normally and sell-through does not. Narrow the range to 90 days or less and it appears. This is documented behavior, not an account or subscription problem.

Does Terapeak work for Amazon sellers?

No. Before the acquisition, Terapeak sold analytics covering more than one marketplace. After eBay brought it in-house, the non-eBay data was retired and the tool became eBay-only. It reports on eBay transactions and nothing else. If you are sourcing from Amazon to sell on eBay, Terapeak validates the eBay demand side of that trade; the supplier side needs separate tooling.

Can Terapeak research eBay's UK and other international sites?

Yes. The marketplace filter lets you switch the dataset from eBay.com to eBay.co.uk, eBay.de and other eBay sites, and the same metrics are calculated per marketplace. That is genuinely useful when a category is crowded at home and thin abroad, though it is only worth acting on if your shipping setup and handling times can serve those buyers properly.

Does Terapeak show what a Best Offer actually sold for?

Yes, and this is one of its real advantages over the standard sold-listings search. When a seller accepts an offer below the listed price, ordinary search shows the original price struck through without revealing the accepted amount. Terapeak includes the price the item actually sold for, so your averages reflect what buyers paid rather than what sellers hoped for.

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