How Rumble Deals estimates video game value

Catalog and estimate fields are baked during the site build. Sold comps are refreshed in explicit batches through either a visible Brave browser session or Firecrawl, then committed as a dated snapshot. The process is not real-time. Every game page shows the catalog refresh date, and each comp entry retains its own fetch timestamp.

A listing must contain every significant title token after stopwords and Roman numeral equivalents are normalized. It must also be consistent with the product platform and expected US market unless the product name explicitly identifies another region or variant.

Titles naming clearly incompatible regions or platforms are rejected. The current rules include Super Famicom, Famicom, SFC, JPN, Japan, NTSC-J, PAL, EUR, Mega Drive, and Disk System markers where they conflict with the tracked product.

WATA, VGA, and CGC markers classify a listing as graded before any sealed wording is considered. This means a title such as “VGA 85 Factory Sealed” belongs only to graded evidence. Factory sealed, brand new, unopened, and new-in-box markers can enter the raw-sealed tier only when no grader is named. Loose, cartridge-only, disc-only, CIB, complete-in-box, and unboxed markers enter the loose tier.

Clearly labeled lots, bundles, reproductions, replacement packaging, box-only pieces, posters, manuals, and reseals are excluded as non-comparable evidence. Unknown condition titles are not forced into a tier.

Each tier is summarized independently. For four or more prices, a 1.5 times interquartile-range rule removes extreme values from the median calculation. The published low and high retain the observed tier range, and the sample titles shown on the page come only from that same tier.

Sold medians and current listing prices are never averaged. A valid sold-comp median leads. A current listing becomes the estimate only when the matching sold tier is empty, and the page labels that fallback as low confidence.

• High: at least five matching comps and an observed range no greater than 50 percent of the median.
• Medium: at least three matching comps that do not qualify as high confidence.
• Low: one or two matching comps, or a current-listing fallback.
• Unavailable: no matching sold evidence and no current listing price.

A tier with fewer than three sales carries a visible low-sample warning. An empty tier stays empty, even when another condition has expensive sales. If you spot a bad comp, include the game URL, the listing title, and why the platform, region, variant, or condition is wrong.

Rumble Deals may earn a commission from qualifying Amazon and eBay marketplace actions. Affiliate relationships do not change tier membership, sold medians, confidence, or sorting rules. Other retailer comparison links are currently untagged. Read the affiliate disclosure.