METHODOLOGY

Data sources

Prices are TCGplayer aggregate market data, read through tcgcsv.com, snapshotted daily. Population counts and gem rates are PSA population data as tracked by GemRate. Card metadata and illustrator credits come from the open pokemon-tcg-data card database. Graded price references (PSA 10, grade 9, ungraded) come from PriceCharting product pages and are labeled wherever they appear. None of these companies endorse this site.

The movers screen

TCGplayer's market figure is a sales weighted average, which makes it noisy on thin products: one strange sale can double it while the actual market sleeps. A price move only reaches the movers table when it passes three screens. First, the market, low, and mid figures must all have moved in the same direction over the window. Second, rows whose three figures are byte identical across the last three snapshots are treated as stale rather than stable, because the source stopped refreshing them. Third, rows where the market figure sits below 70 percent of the listing low are discarded, because nothing sells at a price below every listing; that shape means the row is broken. Around three quarters of raw "top gainers" fail these screens on a typical day, which matches what a manual audit of listing pages finds.

Pop spike alerts

GemRate publishes each card's total gradings and its growth over the trailing 30 days. The alert list shows established cards, meaning at least 200 gradings before the recent wave, that added at least 50 new gradings in 30 days, ranked by growth relative to their prior base. New sets are excluded on purpose: everything grows fast from zero, and a submission wave on a brand new set is expected rather than informative.

The grading ROI calculator

Expected value is the sum of each outcome times its payout, minus what you paid: the gem outcome pays the PSA 10 price less selling costs, the grade 9 outcome pays the grade 9 price less selling costs, and every other outcome is assumed to return your raw price. Odds default to the card's own population distribution, which overstates a random raw copy's chances because people submit their cleanest cards. Grading fees are PSA list prices read from psacard.com on 2026-08-17; PSA changes them, the fee field is editable, and the tier notes carry the caveats. The default selling cost is an editable assumption, not a quoted fee from any marketplace. Prefilled prices pair PriceCharting's ungraded figure with PriceCharting's graded figures so both sides of the spread describe the same product; mixing price sources across a spread invents money.

The sealed index

Sealed listing stacks on TCGplayer are contaminated: foreign product and accessories get listed under the English product id, so the cheapest listing on a $400 booster box page can be a $40 slim box from another market. The index therefore quotes only the aggregate market figure and never a listing floor. The scenario modeler makes no predictions; it compounds an assumption you type in, and shows the same money at your own benchmark next to it.

The artist tracker

Illustrator credits come from the printed card, via the open card database. Population totals for an artist pool every tracked print of each illustration, including Japanese and other language prints, because the illustration is the artist's regardless of print run. Per card prices shown on artist pages are for the English base print unless labeled otherwise. Artists are ranked by total graded population, which measures what the market actually submits rather than what anyone thinks of the art.

Known limits

Price history on this site starts 2026-08-08, so trend windows longer than the archive cannot be shown yet; they grow daily. Population data covers PSA only. Foreign print prices frequently do not exist as separate products at any source, and those cards honestly show no price rather than borrowing the English one. And everything here describes markets that are thin next to any real asset class: spreads are wide, selling takes time, and past growth is not a forecast.

Disclaimer

Pokemon Predictor is an information tool, not an investment adviser. Nothing on this site is a recommendation to buy or sell anything. Graded cards and sealed product are speculative collectibles with real liquidity risk. Names and trademarks belong to their owners; this site is not affiliated with Nintendo, The Pokemon Company, PSA, TCGplayer, or GemRate.