A free distribution of tokens to wallet addresses, typically used by crypto projects to bootstrap adoption, reward early users, or distribute governance rights.
Airdrops deliver tokens directly to cryptocurrency wallets, usually requiring no direct payment. The mechanism is used for several purposes: rewarding early users of a protocol before its token launches (retroactive airdrops), incentivising users to try a new product (claimable airdrops), forking an existing blockchain and distributing the new asset proportionally to existing holders (hard fork airdrops), and distributing governance tokens to decentralise protocol control.
The most significant airdrops in DeFi history have distributed hundreds of millions of dollars in value. Uniswap's 2020 airdrop sent 400 UNI tokens (worth ~USD 1,200 at launch, peaking over USD 12,000) to every address that had ever used the protocol. Arbitrum's 2023 ARB airdrop distributed tokens worth USD 1–10,000+ to eligible wallets. These events created a professional class of 'airdrop hunters' who systematically interact with new protocols in hopes of qualifying for future distributions.
For traders, airdrops create specific dynamics. Token recipients who received the airdrop at no cost have a zero cost basis, meaning any sale is pure profit - this creates substantial sell pressure immediately after an airdrop becomes claimable, as recipients who have no long-term conviction dump their allocation. Prices often decline sharply in the first hours after a major airdrop opens for claims, then may stabilise once the initial sell wave clears.
Worked Example
A user interacted with 14 DeFi protocols on Arbitrum over six months before the ARB token launch in March 2023. They qualified for 1,475 ARB tokens. ARB opened at USD 1.25 on its first trading day, making the airdrop worth USD 1,844. Since the cost basis was zero (no purchase required), selling at any price represented pure profit. This incentivised immediate selling - which, combined with millions of other recipients doing the same, contributed to ARB declining 30% in the week following launch before eventually finding a base.