Data sources

Every figure on this site traces to one of the rows below. Where a figure is not yet verified, this page says so rather than leaving you to assume it is.

Sources behind the current build, with their verification state.
SourceWhat it supplies State
PriceChartingPer-grade prices, sale volumes and PSA populations for Charizard #4 Fetched 1 Sep 2026
Heritage AuctionsAuction lot records with permanent lot pagesLot URLs verified
Fanatics CollectAuction lot records, first-party pricesLot URLs verified
GoldinAuction lot recordsLot URLs verified; some prices behind sign-in and shown as "price at source"
metals.devLondon PM gold price, the unit every ounce figure divides by Unverified. The current reference is a prototype constant; the backfill has not run.
Pyth NetworkThe live metals strip at the foot of the page — display only Unverified. Never executed against the live service from this build.

What is synthetic in this build

PROTOTYPE. Current per-grade prices, volumes and PSA populations are real (PriceCharting, fetched 2026-09-01); the sold-comps table is real auction records (Heritage, Fanatics Collect, Goldin, PriceCharting sold feed). The daily price HISTORY is synthetic — real daily history cannot exist yet and is accumulated, never backfilled — and is labelled on the chart. The gold reference price and the active-listings module are synthetic.

Corrections

Send the page link and the sale we missed or miscounted. Accepted corrections land in the methodology revision log with a date.