An eBay Marketplace Insights alternative

The approval wall

eBay's Marketplace Insights API returns 90 days of sold item data, and it is the API eBay points to since findCompletedItems was retired. Access is a limited release: you apply with a business case, approval is restricted to selected partners, and new applicants are routinely declined or waitlisted. If your application is one of them, this page is the workaround.

Same workflow, no application

CompsAPI is keyword search over completed eBay sales, returned as JSON from one GET request. There is no eBay developer account, no business case review and no quota negotiation. The free tier is 100 requests a month with every filter enabled, and paid plans scale to 1,000,000 requests a month.

The request

An item_sales style search translates directly: the keyword goes in q, condition filters become condition, and the date range becomes days. Each row carries title, price, last_sold, format, shipping_cost, item_id and url.

curl -G https://api.compsapi.com/v1/sold \
  -H "Authorization: Bearer YOUR_KEY" \
  --data-urlencode "q=charizard psa 10" \
  --data-urlencode "days=1095" \
  --data-urlencode "best_offer=1"

Where it goes further

Marketplace Insights stops at 90 days. With days=1095 CompsAPI pages through up to three years of sold history, which turns the same integration into seasonality charts, depreciation curves and launch analysis. And on Best Offer sales the price field is the amount the sale closed at, so offer heavy categories price correctly. For a one call answer, /v1/comps returns the cleaned median, the spread and the newest matches for a query.