Ethereum Architect: Bitcoin 51% Attack Costs $10 Billion

Ethereum Merge architect Justin Drake has asserted that launching a 51% attack on Bitcoin would be more cost-effective than doing so on Ethereum. Drake, who led the work on Ethereum’s proof-of-stake (PoS) implementation and was a principal architect in the Merge, stated that it would be “much cheaper to 51% attack Bitcoin” and estimated the cost to be “on the order of $10 billion.”

Drake’s remarks align with a previous statement by Grant Hummer, the co-founder of Ethereum-focused marketing and product company Etherealize. Hummer had claimed that Bitcoin’s security budget makes it vulnerable, estimating that a successful 51% attack would cost $8 billion and become virtually certain when the cost drops to $2 billion. A 51% attack occurs when a single entity or group controls over 50% of a blockchain network’s mining or staking power, gaining control over the network.

Drake explained that to achieve 100% control of the Ethereum chain, an attacker would need 50% + 1 of the stake. He acknowledged that while this would be extremely difficult and expensive, it is not impossible. “A rich nation state can probably pull it off,” he said. At the time of his statement, there was 34,168,987 staked Ether (ETH) worth nearly $89.6 billion, making half of all ETH worth almost $44.8 billion.

However, the actual cost of an attack on Ethereum would likely be much higher. Ether has a current market cap of $316 billion. The ETH needed for an attack is worth nearly 14.2% of the market cap. An undertaking of that size would likely cause a significant ETH price appreciation, further increasing the cost of the attack.

Matan Sitbon, the founder and CEO of blockchain interoperability developer Lightblocks, highlighted that Ethereum has additional defenses against such attacks. “Ethereum’s ultimate security lies not solely in cryptography or protocol rules, but in the community’s powerful social and economic coordination mechanisms,” he said. Drake also pointed out that Ethereum’s PoS system allows the social layer to identify and socially slash an attacker, a feature not available in Bitcoin’s proof-of-work (PoW) consensus mechanism.

Pavel Yashin, Researcher at P2P.org, noted that if centralization is detected, the community could resolve it with a new fork, rendering the old token delisted and the compromised chain irrelevant. Hassan Khan, CEO at Bitcoin liquidity protocol Ordeez, stated that while a 51% attack is theoretically possible, the barriers in practice are extremely high. For Bitcoin, the necessary amount of computing power and energy makes a sustained attack highly improbable, while for Ethereum, PoS introduces additional economic and governance deterrents.