It is important to note that just because an NFT is rare doesn’t mean that it is valuable. NFTs are high-speculative assets, and a wide array of factors can affect their perceived value.
What that said, when selecting an NFT to buy, the rarity of that NFT can play a part in its perceived value. Popular NFT collectibles, such as CryptoPunks and Bored Apes, have a variety of traits that can make them more or less rare than other NFTs in the same collection – and can therefore affect the perceived value.
There are a number of tools that can help you discover the rarity of an NFT. Popular examples include OpenRarity, Rarity Sniper, and NFT Stats. These often use different algorithms – or compile scores from multiple sources – to establish a rarity score for each NFT in a collection.