How DeckSpec Prices Cards

Every card on DeckSpec carries two numbers, and the difference between them is the whole point of the site.

The first is the market price — the raw, current figure a marketplace is showing. It's useful, but it's noisy: a single unusual sale, a mispriced listing, or a quiet trading day can jerk it around. If you've ever watched a card's “price” swing 20% overnight and known nothing really changed, you've seen the problem.

The second is the DeckSpec price, a smoothed composite built to answer a calmer question: what is this card actually worth right now? Four things go into it:

• A trailing 30-day window. We look at a month of observations, not just today's snapshot, so a one-day blip can't define the value.
• Outlier trimming. Abnormal highs and lows are discarded before averaging, so a single $500 “buy it now” on an otherwise-$40 card doesn't drag the number up.
• Recency and reliability weighting. A reading from yesterday counts more than one from three weeks ago, and more dependable sources count more than thin ones.
• Per-finish calculation. Nonfoil, foil and etched are priced separately — because they're genuinely different cards — and shown in USD.

Where the data comes from

For Magic, the catalogue and prices come from Scryfall (which republishes TCGplayer and Cardmarket daily), with MTGJSON for price history and Star City Games for sealed product. Pokémon, Yu-Gi-Oh!, One Piece, Riftbound and Lorcana come through the apitcg catalogue. Non-USD prices are converted using the live European Central Bank EUR→USD reference rate, so a Cardmarket-only card isn't a raw euro figure mislabelled as dollars.

How often it updates

Everything refreshes on a nightly sync, so card, set, most valuable and trending pages all reflect the same daily snapshot. We'd rather show you the plumbing than hide it.

“Indicative, not offers”

DeckSpec is a reference, not a marketplace. Our prices are an honest estimate of value; they are not offers to buy or sell, and no card here is for sale. Use the DeckSpec price to sanity-check a trade, value a collection, or decide whether a deal is fair — then confirm the live number wherever you actually buy or sell.

Everything else on the site is built on this one number: the movers boards rank cards by how much their DeckSpec price has changed, and the sealed worth-opening estimates are built from the per-rarity DeckSpec prices of a set's singles. For the full method, see About & pricing methodology.