What Is A 51% Attack, And How Can It Affect A Blockchain?
A 51% attack happens when a single entity or group gains control of more than 50% of the total hashing power (in PoW) or stake (in PoS) in a blockchain network.
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🕒 8:30 AM
📅 Apr 21, 2025
✍️ By PCODATH
A 51% attack happens when a single entity or group gains control of more than 50% of the total hashing power (in PoW) or stake (in PoS) in a blockchain network. This gives them significant power to manipulate the network.
What Can a 51% Attacker Do?
👉Double Spend Coins.
👉Block Transactions.
👉Monopolize Mining Rewards.
What a 51% Attacker Cannot Do:
👉Steal coins from other wallets.
How to Prevent 51% Attacks:
👉Increase network size and decentralization.
👉Use PoS or hybrid models which are less vulnerable.
👉Add checkpointing or other consensus rules to limit reorg depth.