How we calculate prices.

Every price on CardPricer is derived from publicly observable marketplace activity — we do not estimate, simulate, or fabricate prices. If there's no recent comp, we say so.

• On-chain sales (Collector Crypt, Magic Eden) — USDC-settled prints with Solscan audit links. These are our highest-trust comps.
• Sports card market data — per-grade prices and sales pace are sourced from SportsCardsPro, which compiles them from completed marketplace sales. We snapshot these daily to build our own price history.
• TCG aggregators — Scryfall (Magic), Pokémon TCG API / TCGdex (Pokémon), YGOPRODeck (Yu-Gi-Oh), and OPTCG API (One Piece) for catalog data and prices tagged as quote, not sold prints. Card scans and data are © their respective publishers; CardPricer is not produced by or endorsed by them.
• eBay — Marketplace Insights sold data when available; active asks from Browse are stored separately as listing observations so we never confuse an ask with a sale.

PWCC, Goldin, COMC, and TCGplayer sold feeds are on the roadmap. Each comp row records its source and observation_type so the provenance panel can show exactly what you're looking at.

1. Listings are pulled. A scheduled job queries eBay for a tracked search (e.g. “Luka Doncic Prizm”) and stores raw listings.
2. Listings are normalized. Each listing is matched to a card row by year, set, card number, and grade. Listings that can't be confidently matched are dropped rather than guessed.
3. Current price = recent observed average. The card'scurrent_price is the mean of the most recent qualifying comps for that exact card and grade. Outliers outside a sane band are excluded.
4. Changes are computed against history. The 7-day and 30-day price changes compare today's rolling average to the rolling average from N days ago. No marketing fluff.

The price refresh job runs daily. Hover any sparkline to see the most recent 30-day window of comps for an asset. If a card hasn't had a sale in a while, the sparkline will be flat — that's the truth, not a bug.

On a card detail page, you can also see live (active) listings on the right. Those are asks, not sales — we mark each listing with a delta vs our mid-market so you can spot obvious overpricing or genuine deals at a glance.

We use two distinct numbers and we name them honestly:

• Listed value = Σ current_price across every card we track in a category. It is the size of the bid we currently observe — not a true market capitalization, because we don't yet ingest population (PSA / BGS / SGC pop counts) for every card.
• 30D notional volume = Σ price × sales_volume_30d. The dollars that actually changed hands in the last 30 days — closer to a real-economy “turnover” metric.
• True market cap = Σ population × price. We are actively building toward this — pop-report ingestion is on the roadmap. When it ships, the headline number on each player folder and category view will use this formula; listed value and 30D volume stay as supporting metrics.

• We don't accept payment to surface, hide, or boost any card or seller. There are no paid placements on deal lists or in search results.
• We don't set or recommend prices. We report the prices the market is paying.
• We don't guarantee that any individual card will sell at the displayed price. Comps are a baseline, not a quote.

CardPricer is free and ad-free. When you click an outbound link to eBay from a deal list, a card detail page, or a player profile, that link includes our eBay Partner Network ID. If you end up buying through that link, eBay pays us a small commission at no extra cost to you.

That's the entire revenue model right now. Critically, the commission does not depend on what you buy or who from — so we have no incentive to push you toward any particular listing. See our affiliate disclosure for the full version.

Every number on this site is available over a free public API. The same provenance, confidence scoring, and comp breakdowns that power the front end are exposed at /api/v1/* with open CORS and a generous anonymous rate limit. No signup required to start.

Read the API docs →

Bad data on a comp-driven site is inevitable — eBay listings include misgrades, counterfeits, and the occasional wildly-priced auction. If you notice something off, email hello@cardpricer.app with the URL and we'll investigate.