Glossary

Proof of Stake

Plain-language definition Crypto glossary

Key takeaways

Proof of Stake is a consensus mechanism in which validators are chosen to propose and confirm blocks based on the amount of cryptocurrency they lock up as collateral, rather than on computing power.
Validators deposit a minimum stake and are selected pseudo-randomly weighted by stake size; honest behaviour earns rewards while provable dishonesty can have part of the stake "slashed."
It uses a tiny fraction of the energy of proof of work and lowers the hardware barrier, though critics note it can concentrate influence among the largest stakeholders.

Definition

Proof of Stake is a consensus mechanism in which validators are selected to propose and confirm blocks based on the amount of cryptocurrency they lock up, or “stake,” as collateral rather than on computing power.

How it works

Validators deposit a minimum amount of the network’s token into a staking contract. The protocol then pseudo-randomly chooses who proposes the next block, weighting selection by stake size and other factors. Honest behaviour earns staking rewards; provably dishonest behaviour can have part of the stake “slashed,” giving validators a direct financial reason to follow the rules.

Why it matters

Because it replaces electricity-intensive mining with economic collateral, Proof of Stake uses a tiny fraction of the energy of proof of work. It also lowers the hardware barrier to participation. Critics note it can concentrate influence among the largest stakeholders, which networks counter with delegation and validator limits.

Example

Ethereum moved from Proof of Work to Proof of Stake in 2022. Cardano, Solana and Avalanche are also stake-based networks.

FAQ

Frequently asked questions

How is Proof of Stake different from Proof of Work?

Proof of Work secures the network through energy-intensive mining, where computing power decides who adds a block. Proof of Stake replaces that with economic collateral, selecting validators by the amount they stake, which uses far less energy and lower-cost hardware.

What is slashing?

Slashing is the penalty that removes part of a validator's staked collateral when they provably break the rules. It gives validators a direct financial reason to behave honestly, since misbehaviour costs them real money.

Does Proof of Stake have any downsides?

Critics point out that selecting validators by stake size can concentrate influence among the largest holders, since more stake means more say. Supporters argue its energy efficiency and lower hardware barrier broaden participation; the trade-off is an ongoing debate.