Pokémon card prices are driven by supply and demand: rarity, playability, condition, and popularity of the Pokémon or art. Market prices are often tracked via major marketplaces (e.g. TCGPlayer, eBay, Troll and Toad) and can be quoted as low, market, or trend.
Vintage cards (Base Set, early promos) and modern chase cards (alternate arts, illustration rares) can reach hundreds or thousands of dollars in top condition. Grading (PSA, BGS, CGC) can add a premium. Prices fluctuate with new set releases, meta shifts, and collector trends.
Checking current prices before buying or selling helps you make informed decisions and avoid overpaying or underselling.