Proof of Stake

Proof of Stake (PoS) is a consensus mechanism used by many blockchain networks to validate transactions and create new blocks. Instead of relying on computational power as in Proof of Work (PoW), PoS selects validators based on the amount of cryptocurrency they lock up, or “stake,” as collateral. The larger the stake, the higher the chance of being chosen to propose the next block, though randomisation and other factors prevent wealth concentration from dominating the process.

How It Works

Participants who wish to become validators first deposit a predetermined amount of the network’s native token into a special smart contract. This stake acts as a security deposit that can be slashed, or partially forfeited, if the validator behaves dishonestly or fails to perform its duties. When a block needs to be added, the protocol pseudo‑randomly selects a validator, weighting the selection by the size of each stake and often incorporating factors like coin age or a randomised hash. The chosen validator checks the transactions in the block, signs it, and broadcasts it to the network. Other validators then attest to the block’s validity; once enough attestations are collected, the block is finalised and the proposer receives a reward, typically consisting of newly minted coins and transaction fees.

Why It Matters

PoS drastically reduces the energy consumption required to secure a blockchain, addressing a major criticism of PoW systems. For example, Ethereum’s transition to PoS in 2022 cut its annual electricity use by approximately 99.95%, making the network far more environmentally sustainable while maintaining security and decentralisation. Lower barriers to entry—users need only hold and stake tokens rather than invest in expensive mining hardware—also broaden participation, fostering a more inclusive validator set and enhancing the network’s resilience against attacks.