Lab — Devtool

NFT Rarity Calculator

NFT Rarity Calculator is a free online tool that scores how rare each item in a collection is from its traits — paste your collection as JSON and get trait frequencies, rarity scores and a ranked leaderboard, computed entirely in your browser. Nothing is uploaded.

Your collection (JSON)

Format: an array of items, each with an id and a traits object, e.g. [{"id": 1, "traits": {"Background": "Blue", "Eyes": "Brown"}}]

How rarity is calculated

For each trait value: frequency = items with that value ÷ collection size.
Each trait scores 1 ÷ frequency — a value held by 1 of 12 items scores 12.00.
An item's rarity score is the sum of its trait scores; the highest score ranks #1.
Caveat: this is trait rarity, not market value. A rare trait does not guarantee a higher price.