Cost of a 51% attack
Hardware cost only, at cheapest rateThe attack would consume 128,194,990 kWh per day (6,409,749$ per day)
The benefits of a 51% attack are detailed on our page How does Bitcoin works?.
- The attacker is starting from scratch. This does simulate the case where the attacker a mining pool.
- The attacker has no ability to get hardware cheaper than the current best offer. The attacker could for example be a hardware manufacturer.
Earnings / Opportunity cost
During a 51% attack, the attacker has to create blocks on two separates chains. He would thus lose the bitcoins mined on the first shorter chain.
By using the hardware necessary for such an attack with honesty, the attacker could earn 918 BTC per day.
This is a simple simulation and does not take into account any other attack vectors.