An ERC-20 token on Ethereum that represents Bitcoin 1:1, allowing BTC holders to use their Bitcoin in Ethereum's DeFi ecosystem. Each WBTC is backed by one real Bitcoin held in custody by a custodian.
An ERC-20 token on Ethereum that represents Bitcoin 1:1, allowing BTC holders to use their Bitcoin in Ethereum's DeFi ecosystem. Each WBTC is backed by one real Bitcoin held in custody by a custodian.
Wrapped Bitcoin (WBTC) is a tokenized version of Bitcoin that lives on the Ethereum blockchain as an ERC-20 token. Each WBTC token is backed 1:1 by actual Bitcoin held in reserve by a custodian (originally BitGo). The wrapping process involves depositing BTC with the custodian, who mints an equivalent amount of WBTC on Ethereum. To unwrap, the process reverses — WBTC is burned and BTC is released. This bridge allows Bitcoin holders to access Ethereum's DeFi ecosystem without selling their BTC.
WBTC has become one of the most significant bridges between the Bitcoin and Ethereum ecosystems, with billions of dollars in BTC locked in the wrapping protocol. The primary use cases include lending Bitcoin on DeFi platforms like Aave and Compound (earning yield on BTC), using BTC as collateral for stablecoin loans, and providing liquidity in decentralized exchanges. These activities were impossible with native Bitcoin, which lacks Ethereum's smart contract functionality.
However, WBTC introduces trade-offs that Bitcoin purists find unacceptable. The custodial model requires trusting a centralized entity to hold the backing Bitcoin — a direct contradiction of Bitcoin's trustless ethos. If the custodian is compromised, the WBTC could become unbacked. Newer solutions like tBTC and sBTC aim to decentralize the custodial process, but WBTC remains the most liquid and widely adopted wrapped Bitcoin token. Investors must weigh the DeFi utility against the counterparty risk.
A user deposits Bitcoin with a custodian, who verifies the deposit and mints an equivalent amount of WBTC on Ethereum. The Bitcoin is held in reserve, and the WBTC circulates freely on Ethereum as an ERC-20 token. To redeem, a user burns their WBTC, and the custodian releases the underlying Bitcoin. The reserves are transparently auditable on both blockchains.
WBTC is as safe as the custodian holding the underlying Bitcoin. If the custodian is compromised — through hacking, insolvency, or regulatory seizure — the WBTC could lose its peg. Smart contract risk also exists on the Ethereum side. While WBTC has operated securely since 2019, the custodial dependency is a meaningful risk that does not exist when holding native Bitcoin in self-custody.
The primary reason is to earn yield on Bitcoin through DeFi protocols. Native BTC sitting in a wallet generates no return, but WBTC can be lent on platforms like Aave for interest, used as collateral to borrow stablecoins, or provided as liquidity in decentralized exchanges for trading fees. These DeFi strategies can generate 1-10%+ annual yield on Bitcoin holdings, though they introduce smart contract and custodial risks.