Two independent price pipelines, cross-checked.
Every card is priced from two unrelated markets that cannot copy each other's mistakes: Europe (Cardmarket, EUR) and the United States (TCGplayer and PriceCharting, USD). Both prices are shown side by side on every card, labelled by source and method — never blended into one number. When they disagree beyond what FX and condition explain, the number is flagged instead of published.
Suspicious numbers don't ship.
Incoming prices pass automated sanity gates before they reach the site. A value that moves implausibly against its own history is quarantined and the previous verified value is kept — a stale-but-true number beats a fresh-but-wrong one. Database-level triggers block known contamination patterns from ever writing.
Where data is thin, we say nothing. A card without a reliable PSA population or without real graded sales gets no grading verdict — not an estimate, not a model guess. Silence over speculation, everywhere on the platform.
What the score weighs.
Each card's investment score combines six measured dimensions: market liquidity (how often it actually sells), scarcity (its real PSA population), era effects (how its print generation has historically behaved), tradability (spread, fees, and how hard the position is to exit), character premium (the measured market preference for certain Pokémon), and price momentum. The exact weights and curves are proprietary — the inputs are not, and each card page shows its sub-scores so you can see why a card ranks where it does.
What the letters mean.
Every card's composite score maps to a letter, S+ down to D. The letters are percentile bands across all 24,000+ scored cards, not opinions: a card earns its letter by where its measured profile sits in the whole population, and the letter moves when the data moves.
A grade is a snapshot of measured market structure, not a prediction. Grades are recalculated as prices, populations and sales flow in, and each card page shows the sub-scores behind its letter so you can see exactly why it sits where it sits.
Priced on the grades you'll actually pull.
The grade-or-sell verdict does not assume you hit a PSA 10. It uses each card's own population report as the realistic grade mix — most submissions come back a 9, not a 10 — prices every outcome at its actual sold value, then subtracts a ~$25 grading fee and a 13% selling cost. Cards with fewer than 30 graded copies get no verdict: the grade mix would be a guess, and we don't publish guesses. The same function produces the verdict on card pages, the leaderboard, and the grading calculator — they can never disagree.
We test our own claims before you read them.
In June 2026 we backtested the ranking system against five years of monthly price history: 6,470 cards, walk-forward splits that train on the past and are graded on a future the model never saw, plus an adversarial review pass designed to kill weak conclusions. The finding: the relative ranking holds out of time. Cards ranked higher went on to outperform cards ranked lower in every split we tested, a real but modest edge that survives clustering, re-sampling and regime changes.
The same tests define what we refuse to claim. A precise multi-year percent return is not predictable for a single card, which is why card pages lead with the tier and present returns as a range around a midpoint instead of a decimal promise.
Validation is not a one-time exercise. Every deal signal our engine posts is logged in a public ledger with its entry price, its market reference, and what prices did next, hits and misses alike. The record is the argument.
What we refuse to publish.
No hypothetical performance — you will never read "if you had bought X you'd be up Y%" here. No urgency manufacturing. Projections are statistical estimates from historical data, labelled as such, and may be wrong. Research characterises what the market is doing; it does not instruct you to act. And when the data can't support a claim, the claim doesn't appear.
Questions about the data? [email protected]
Common questions about the data.
Does TCGinvest show both Cardmarket and TCGplayer prices?
Yes. Every card page displays the European Cardmarket price alongside US prices from TCGplayer and PriceCharting. Prices remain separate and are clearly labelled by source.
Can I compare European and US Pokémon card prices?
Yes. TCGinvest was built specifically so collectors can compare European (EUR) and US (USD) prices without converting or averaging them.
Why doesn't TCGinvest combine the two prices into one number?
European and US markets genuinely behave differently — across the cards we track in both, European sold prices run well below US ones on average. Keeping them separate lets collectors compare both markets directly instead of trusting a blend that describes neither.