How a PokéTT price is made

• It’s a median, not a last sale. One unusually high or low sale can’t move the price much — the middle value of the recent sales does.
• Grades are never mixed. A raw copy, a PSA 9 and a PSA 10 of the same card each get their own price, from their own sales only.
• A price is either a real sale median, or clearly labelled as something else — a reference/guide value, or “not enough reliable sales yet”. We never blend the two.

Sold listings from eBay, Yahoo! Auctions Japan, Mercari and TCGplayer feed every median on the site. PriceCharting is used differently: its per-grade guide values fill in a grade that has zero real recorded sales, clearly marked as a reference (an asterisk and “ref” in the UI) — a guide price is never averaged or blended into a real-sale median, and never counts toward the “3 real sales” a price needs to be stated as fact (see below).

• Each sold listing’s title is parsed for the card’s name, set, collector number and grade — including odd phrasing, half grades (9.5), and grading companies beyond PSA (BGS, CGC, SGC, TAG, ACE, ARS).
• Distinct print variants are kept separate. An English 1st Edition, Shadowless and Unlimited copy of the same card are three different prices, not one blended average — matching the exact variant the listing describes.
• Language is never merged. A Japanese and an English print of the same card are always two separate prices.
• A listing that can’t be pinned to one exact card — a lot of several cards, a seller’s stock photo reused across many listings, a title that matches more than one print — is left out of every card’s price rather than guessed at.
• A sale that’s later found to be wrong (sealed box mis-scanned as a single card, a typo’d listing, and so on) can be excluded by us — reversibly, never by deleting the underlying record — after review.

A grade’s price is only stated outright (in a card’s headline, a quick-answer sentence, or a search snippet) when it has at least 3 real, non-reference sales in the last 12 months and makes sense next to the card’s other grades — a higher grade should never price below a lower one by more than a small margin, and a raw price sitting absurdly far below a five- or six-figure graded reference is treated as mismatched sales, not a genuine bargain. When a grade fails either check, we say so instead of guessing: “rests on a single recorded sale”, “too few reliable sales”, or similar — never a number we can’t stand behind. The full list of every recorded sale still shows on the card page either way, so nothing is hidden — only what we state as fact is gated.

• High — 10 or more real sales, the newest within roughly the last 3 months.
• Medium — 3 or more real sales, the newest within roughly the last 6 months.
• Low — thinner or older than that. Still real sales — just fewer of them.
• Reference — a price-guide figure, not a recorded sale (see “Where the sales come from” above).

You’ll see this as a small dot next to a grade’s price on the card page.

• Graded market cap — measured inputs. For every card, each grade’s price (the sale medians above) × the number of copies PSA, CGC and BGS report in that grade. If a card’s graded total comes out implausibly far above its raw price × its graded copies (a sign of one bad graded sale), we use raw price × graded copies for that card instead of trusting the outlier.
• Total market cap — a PokéTT proprietary estimate. The graded value above plus an estimate of the ungraded copies × the raw price. No public print-run figures exist for Pokémon cards, so the number of ungraded copies is modelled from the graded population: we assume the share of copies that get graded rises with a card’s value (cheap cards are rarely graded, expensive ones mostly are) and is higher for cards that are already graded in large numbers. The curve and its coefficients are PokéTT’s own, chosen by us, not taken from any outside source.
• How to read it. Wherever the total figure appears (set rankings, “Top Sets”) it is labelled estimated. Treat it as an order-of-magnitude view of where value sits, not a count — the graded market cap is the measured figure.

The is-it-worth-grading calculator is built on the same real sold prices above, plus PSA’s published population report for the exact card and a discount on the reported gem rate — the method for that specific tool is on its own page.