TCG Price Arbitrage - Cardmarket vs TCGplayer

Compares the European market price (Cardmarket, EUR) against the US market price (TCGplayer, USD) for the Pokémon cards you search - matched card by card via collector number, converted at the daily ECB rate, and delivered as spread rows sorted by the biggest gap. One run answers: which of these cards are meaningfully cheaper on one side of the Atlantic?

Quick start

1. Type a search: "umbreon gx", "charizard vmax", "pikachu promo".
2. Run. Rows come back like:

{
  "name": "Umbreon GX  (SUM 80)",
  "cardNumber": "80",
  "setNameUs": "SM Base Set",
  "trendEurCardmarket": 27.66,
  "marketUsdTcgplayer": 26.66,
  "marketUsdInEur": 22.9,
  "spreadPct": 20.8,
  "cheaperSide": "US",
  "eurPerUsd": 0.8589,
  "urlCardmarket": "https://www.cardmarket.com/en/Pokemon/Products/Singles/SM-Base-Set/Umbreon-GX-SUM80",
  "urlTcgplayer": "https://www.tcgplayer.com/product/126952",
  "priceGuideDate": "2026-08-28"
}

How the comparison works

• EU side: Cardmarket's official daily price guide (trend and 30-day average) plus the live cheapest listing.
• US side: TCGplayer's market price and lowest listing, from its public storefront search.
• Matching: cards are joined by name and collector number (SUM 80 = 80/149). Ambiguous or numberless matches are dropped rather than guessed - a wrong match would fake an arbitrage.
• Currency: USD prices are converted at the daily ECB reference rate (override with eurPerUsd if you hedge differently).

FAQ

Which direction does it report? Both. cheaperSide says which market is cheaper for each card; spreadPct is the gap as a percentage of the cheaper price. Sort or filter as you need.

Does the spread include shipping, customs and fees? No - it is the raw market-price gap. Cross-border selling costs (shipping, marketplace fees, possible import duties, grading) are yours to subtract; that is why the default threshold is 20%, not 5%.

Why only Pokémon? The card-number matching that keeps results trustworthy is verified for Pokémon's numbering. More games follow once their matching is equally reliable.

Why did a card I expected not appear? Either its trend price is under priceMinEur, the spread is under your threshold, or the card could not be matched unambiguously across the two markets - unmatched is silent by design, never guessed.

How fresh is the data? Cardmarket prices are from today's official price guide; TCGplayer prices and the ECB rate are fetched live at run time.

Any seller data involved? None. Both sides are aggregate market prices - no listings, no seller identities.

Can I run it on a schedule? Yes - daily runs per niche query make a continuous spread monitor. Pair it with the Cardmarket Deal Finder to act on the EU side of a spread.

Something broken or missing?

Open an issue on the Issues tab - it is read daily. More games and sealed-product coverage are on the roadmap.