A validator is a participant in a Proof-of-Stake blockchain that performs protocol-defined functions for verifying and maintaining network state. Depending on the blockchain, a validator may propose new blocks, vote on blocks proposed by other participants, participate in finalization, or perform other consensus operations.

A validator usually needs a certain amount of its own or delegated stake to participate. This capital acts as economic security for the validator's behavior. Correct and available validators may receive staking rewards, while certain protocol violations or failures may lead to penalties or slashing.

What a validator does

  • maintains a functioning blockchain node;
  • receives and validates network data;
  • participates in block production or confirmation;
  • signs protocol messages when required;
  • maintains reliable network connectivity;
  • monitors software and infrastructure;
  • protects the keys required for validator operations.

Running a validator requires more technical responsibility than simply delegating coins. The operator must maintain a validator node, update software, secure keys, monitor server availability, and respond to network events.

Validator and delegator

A delegator can assign economic weight to a selected validator without operating the infrastructure itself. The validator performs the technical work, while the delegator receives a share of available rewards after the validator's commission and protocol rules are applied.

Choosing a validator therefore involves more than looking at the advertised reward rate. Reliability, commission, operational history, stake concentration, protocol rules, and penalty exposure can all matter. Past performance does not guarantee future results.