What Is a Validator?
A validator is a participant in a proof-of-stake blockchain that proposes new blocks and attests to others’ blocks. Validators stake the network’s native asset, earn rewards for honest work and can be slashed for breaking rules.
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A validator is a participant in a proof-of-stake blockchain that proposes new blocks and checks, or attests to, blocks proposed by others. To take on this role, a validator locks up the network’s native asset as collateral, a process known as staking. Validators that follow the rules earn rewards; those that break them can lose part of their stake.
What does a validator do?
On proof-of-stake networks, the right to produce blocks comes from staked collateral rather than from a computing race as in proof of work. For each slot, the protocol randomly selects a validator to propose a block. Other validators check that block and, if it’s valid, cast a vote known as an attestation. Blocks that gather enough votes are added to the chain and become final after a set period.
- Proposing blocks: bundling pending transactions into a new block.
- Attesting: checking that proposed blocks follow the rules and voting on them.
- Staying online: remaining available around the clock to perform duties on time.
What do you need to become a validator?
Requirements vary by network. Running your own validator on Ethereum takes 32 ETH as stake, a computer that’s always on and both an execution client and a consensus client. Networks such as Solana, Cardano and Avalanche have their own stake and hardware requirements.
If you can’t meet those requirements, you can still take part indirectly by delegating your coins to a validator, or through liquid staking and exchange staking services. In that case, part of the rewards goes to the validator or service provider as commission. Our staking guide covers the options in detail.
Validator rewards and slashing
Validators are paid for proposing and attesting to blocks, through newly issued coins and transaction fees. The reward rate depends on the total amount staked on the network: the more coins staked, the lower the rate each validator typically earns.
Slashing is the penalty for validators that break the rules. Signing two different blocks for the same slot or casting contradictory votes can lead to part of the stake being destroyed and the validator being removed from the network. Simply being offline for a long time usually results in smaller penalties.
Validator vs node vs miner
Every validator runs a node, but not every node is a validator. Nodes store the chain and enforce the rules; validators also take part in producing blocks. Miners are the proof-of-work equivalent: they spend computing power instead of locking up collateral.
Risks of running or delegating to a validator
Running your own validator means taking on the risk of hardware failure, software bugs and poor key management. When you delegate or use a staking service, the chosen validator’s performance and commission, and the provider’s reliability, are what matter most. On most networks, withdrawing staked funds involves a waiting period, and you remain exposed to price swings while you wait.
How to choose a validator
If you delegate your coins, your choice of validator directly affects your returns and your risk:
- Commission: the share of rewards the validator keeps. The lowest commission isn’t always best; an operator that can’t sustain its business may eventually shut down.
- Uptime: validators that are frequently offline cost you rewards.
- Slashing history: a past penalty can point to operational weaknesses.
- Centralization: stake concentrated in a few large validators weakens a network’s decentralization; backing smaller but reliable operators supports the network’s health.
Frequently asked questions
Is running a validator profitable? Returns depend on the total amount staked, transaction fees, the validator’s performance and the coin’s price. Because rewards are paid in the coin itself, a falling price can wipe out the gains.
Are validating and staking the same thing? Staking means locking coins to help secure a network. A validator is the party that uses that stake to actually take part in block production. Every validator stakes, but not everyone who stakes runs a validator.