A node operator in a Proof of Stake network that validates transactions and proposes blocks by staking tokens as collateral.
A validator is a node operator in a Proof of Stake blockchain who locks up ('stakes') the network's native tokens as collateral and participates in the consensus process — validating transactions, proposing new blocks, and attesting to the chain's state. Validators earn rewards (new tokens + transaction fees) for honest participation and risk losing their stake ('slashing') for malicious behavior or extended downtime. Becoming a validator typically requires a minimum stake (32 ETH for Ethereum, 1 SOL for Solana) plus the technical infrastructure to maintain high uptime. Ethereum has over 900,000 validators, while Solana has roughly 1,500. The validator set is crucial for decentralization — the more independent validators, the harder it is for any entity to control or censor the network. Professional validator operators (like Coinbase Cloud, Figment, and Chorus One) run validators on behalf of institutions and staking pools.
Validators are nodes in Proof of Stake networks that verify transactions, propose new blocks, and maintain consensus by putting up economic collateral (staked tokens) that can be destroyed ('slashed') for misbehavior. Running a validator requires: staking the minimum required tokens (32 ETH for Ethereum, 1 GNO for Gnosis Chain), maintaining reliable hardware and internet connectivity, and keeping validator software updated. Validators earn rewards from block production, attestations, and transaction fees. The validator role is central to PoS security — the honest majority of validators must agree on each block's contents for the chain to progress. Validator economics create a natural balance: high rewards attract more validators (improving security but reducing per-validator rewards), while low rewards cause validators to exit (concentrating power but increasing per-validator rewards). Professional staking operations run thousands of validators across multiple clients for redundancy.
Running an Ethereum validator requires 32 ETH (~$100K+), a reliable computer, and consistent internet — in return, validators earn roughly 3-5% APY while securing a network holding hundreds of billions in value.
For Ethereum: yes, with 32 ETH, a dedicated computer (~$500-1,000 hardware), stable internet, and willingness to maintain the system. For Solana: difficult — high hardware requirements (128GB RAM, fast SSD). Staking without running a validator (delegating to an existing one) is easier and available on most PoS chains.