Validate demand with real transaction data
eBay processes millions of transactions across every product category. SoldComps gives you programmatic access to that sold data — actual prices people paid, not asking prices. Use it to validate product ideas, size markets, and track pricing trends.
Get your API key — freeAsking prices lie. Sold prices don't.
Market research built on asking prices is research built on wishes. eBay asking prices run 30–80% higher than what items actually sell for. The only reliable pricing signal is completed transactions.
eBay is the largest secondhand marketplace in the world. Covers virtually every product category. The sold data is the closest thing to a universal secondhand price index. But accessing it programmatically required either eBay partner approval (which they don't grant) or building your own scraper.
What you can research
Product Demand Validation
Search your product keyword. 240 results in 30 days means strong demand. 50 results over 90 days means niche. The sell-through ratio — sold listings versus active listings — tells you whether supply outpaces demand. Community benchmark: above 70% sell-through is healthy. Below 30% means the market is saturated or the price point is wrong. One API call gives you the sold side of that equation.
Price Range Analysis
Each sold listing includes final price, condition, and date. Filter by condition to find true comparables. Calculate median and percentile ranges to understand the realistic price window. Track price trends over time by making periodic calls and storing results. One keyword search replaces hours of manual browsing through completed listings pages. Useful for reseller pricing and wholesale buying decisions alike.
Competitive Landscape
Seller data comes with every response — username, feedback score, positive feedback percentage. See how many unique sellers compete in a category. High seller concentration means established players dominate. Many sellers with low feedback scores means low barrier to entry. This matters whether you're evaluating a market to enter or sizing a category for a client.
Beyond reselling
SoldComps is used by people who need real transaction data for decisions beyond buying and selling on eBay. Wholesale buyers check sell-through rates before bulk purchases. Product developers validate demand before manufacturing. Category managers benchmark secondhand prices against new-product pricing.
Insurance adjusters look up replacement cost. Appraisers use sold data as Fair Market Value evidence for tax purposes and estate settlements. Common thread: they all need “what did this actually sell for.”
The gap
Asking price
$150
Median sold price
$87
42% lower than asking
Common questions
How much historical data is available?
SoldComps returns the most recent completed listings — typically 60 to 90 days of history. High-volume categories like consumer electronics can return 240 results within a single week. Niche categories with fewer sales may span several months to fill 240 results. The depth depends on how frequently items sell in that category.
Can I track prices over time?
SoldComps returns real-time snapshots of sold data. To track pricing trends, make periodic API calls — daily or weekly — and store the results in your own database. Many users run a cron job to build historical datasets. The API returns a sold date with every item, so you can chart price movement over time from your accumulated data.
Is this just for eBay?
SoldComps covers 8 eBay marketplaces: US, UK, Germany, France, Italy, Spain, Canada, and Australia. eBay is the best proxy for secondhand pricing due to its scale, category breadth, and transaction transparency. Many researchers use eBay comps as a baseline and adjust for other platforms where transaction data isn't publicly available.
Start your research
100 free requests a month. No credit card needed. One endpoint, an API key, and up to 240 recent completed sales per call.