Crypto Gloss

NFT Traits

NFT traits are the individual visual attributes that define a PFP (profile picture) or generative art NFT — categories like background color, body type, head accessory, eye style, and clothing — stored in the NFT’s metadata as JSON key-value pairs, enumerable on marketplaces like OpenSea, and used to calculate rarity scores that drive significant price differentiation within a collection.

Trait Structure

NFT traits are stored in the token metadata as an attributes array:

“`json

{

“attributes”: [

{ “trait_type”: “Background”, “value”: “Blue” },

{ “trait_type”: “Body”, “value”: “Zombie” },

{ “trait_type”: “Eyes”, “value”: “Laser Eyes” },

{ “trait_type”: “Mouth”, “value”: “Grin” },

{ “trait_type”: “Hat”, “value”: “None” }

]

}

“`

This metadata is read by OpenSea, Blur, and other marketplaces to:

  • Display filterable attributes on the collection page
  • Calculate and display rarity information
  • Enable trait-based filtering (show all NFTs with “Laser Eyes”)

Trait Categories

Type-level traits: The category of character

  • Example: CryptoPunks have Type (Human, Zombie, Ape, Alien)
  • Type is often the rarest and most valuable trait category
  • Only 9 Alien CryptoPunks exist out of 10,000

Background traits: The backdrop of the character

  • Usually the most common trait category
  • Background color or scene variation; least impact on price

Core visual traits: The main character definition

  • Body type, skin/fur/scales, base art
  • Mid-range rarity and price impact

Accessory traits: Hats, clothing, accessories, held items

  • Wide variety; some accessories are extremely rare
  • “Special” accessories (pirate swords, laser eyes) command premiums

“None” traits: The absence of an accessory is a trait

  • Example: “Hat: None” — the NFT has no hat
  • Sometimes (counterintuitively) very rare and valuable when the collection mostly has hats

Trait Floors

Each trait type and value can have its own “trait floor”:

  • Trait floor = cheapest listed NFT in the collection with that specific trait
  • Example: “Laser Eyes” floor = 5 ETH; all other “Laser Eyes” holders know their minimum value
  • Marketplaces with trait filtering (OpenSea, Blur) make trait floor tracking possible

Off-chain vs. On-chain Traits

Off-chain metadata (most common):

  • Traits stored as JSON on IPFS or a centralized server
  • Marketplaces read the JSON to display traits
  • Risk: if the metadata server goes down or changes, traits may not display

On-chain metadata (rare but more permanent):

  • Traits encoded directly in the smart contract
  • No external dependency; traits persist as long as Ethereum exists
  • Examples: Autoglyphs, Nouns, Loot

History

  • 2017 — CryptoKitties introduce trait-based NFT breeding; traits become a foundational NFT concept
  • 2021 — CryptoPunks traits (Alien, Ape, Zombie types) become canonical; BAYC’s trait metadata sets the standard for 10,000 PFP collections
  • 2021–2022 — OpenSea’s trait filtering and rarity displays become standard; trait floors emerge as a market concept
  • 2022–2024 — Blur and professional trading platforms add trait-level analytics; traits remain the primary rarity and price driver for PFP collections

Common Misconceptions

  • “All traits are equally important.” — Trait value varies enormously. Type-level rarities (Alien CryptoPunk, 0.09%) are worth orders of magnitude more than common background colors (30%+ frequency).
  • “Traits are stored in the NFT itself.” — For most collections, traits are stored in external JSON metadata linked by the smart contract. The NFT only contains a pointer. Only fully on-chain NFTs have traits embedded directly in the contract.

Social Media Sentiment

  • X/Twitter: Trait reveals are major Twitter moments; “I got [rare trait]” posts are a staple of NFT culture; trait analysis accounts have large followings.
  • r/NFT: Trait rarity questions and trait value debates are high-engagement posts; which traits are most valuable is an ongoing community conversation.

Last updated: 2026-04

Related Terms

See Also

  • NFT Rarity — how traits translate into rarity scores and rankings; rarity is derived from trait frequency
  • NFT Metadata — the technical structure that stores trait data; traits are a key component of NFT metadata
  • NFT Reveal — the event that makes traits visible; before reveal, traits are hidden in unrevealed metadata

Sources