Ethereum is two layers, and explorers mostly show one
Since the Merge in September 2022, Ethereum has had an execution layer, which processes transactions and runs the EVM, and a consensus layer, which decides which blocks are canonical and is secured by staked validators.
Almost every explorer shows you the execution layer, because that is where transactions live. Etherscan will tell you everything about a transaction and nothing about the validator that proposed the block containing it, whether that validator has been attesting reliably, or whether anyone was penalised for anything in that epoch.
beaconcha.in covers the other half. For the roughly one million validators securing the network and the far larger number of people staking through them, that half is the one that determines returns.
Validator performance, and the metric that matters
A validator's job is mostly attesting — voting on what it believes the head of the chain to be, every epoch. Occasionally, roughly once every few months at current validator counts, it is selected to propose a block.
Rewards come mainly from attestations, and specifically from attestation effectiveness: attesting correctly and promptly. An attestation submitted late still counts but earns less. This is the number that separates a well-run validator from a poorly-run one, and it is the number beaconcha.in puts front and centre.
The common causes of poor effectiveness are unglamorous and fixable: a slow or unreliable connection, an overloaded machine, clock drift, or an execution client lagging its consensus client. The explorer will show you the symptom; the cause is on your hardware.
Proposal history matters less statistically but more financially in the moment, since a proposed block carries priority fees and any MEV payment. Missing a proposal because your node was down is the most expensive single failure available to a solo staker.
Slashing, which is rarer than people fear
Slashing is the penalty for provably malicious behaviour — signing two conflicting blocks, or two conflicting attestations. It results in a penalty and forced ejection.
It is worth being clear, because the fear is out of proportion to the risk: slashing is rare, and it is essentially never caused by downtime. Being offline costs you the rewards you would have earned, roughly the amount you would have gained, and nothing more. Slashing requires signing contradictory messages, which in practice almost always means running the same validator keys on two machines at once.
The single most reliable way to get slashed is a badly executed failover — moving a validator to new hardware without ensuring the old one is truly stopped. beaconcha.in records every slashing event with its reason, and reading a few of them is an education in what actually goes wrong.
A useful habit
If you stake, set up the downtime alert. Missed attestations accumulate quietly and a solo validator can be offline for days before anyone notices. The alert is free and it is the highest-value two minutes of configuration available to a staker.
Withdrawals since Shapella
The Shapella upgrade in April 2023 enabled withdrawals from the consensus layer, which changed staking from a one-way commitment into something with an exit.
Two kinds exist. Partial withdrawals sweep the balance above 32 ETH automatically and periodically, with no action required — that is your accumulated rewards arriving. Full withdrawals require exiting the validator, which puts it in a queue whose length depends on how many others are exiting at the same time.
beaconcha.in tracks both, including the exit queue position. For anyone planning to unstake, that queue is the answer to "when", and it is not a fixed number — it lengthens sharply during periods when many validators exit together.
One prerequisite catches people out: withdrawals only work if the validator has withdrawal credentials pointing at an execution-layer address. Validators set up in the early days often used the older BLS credential format and must be updated first. beaconcha.in shows the credential type on the validator page, and checking it before you need it is considerably better than checking it afterwards.
API and self-hosting
A free API tier with a key covers validator status, performance and rewards — enough for a personal dashboard, tight for anything larger. Paid tiers exist.
It is also open source and self-hostable, which is unusual for a tool this specialised. If you run a beacon node already, running the explorer against it is a natural extension and removes the third party from your monitoring entirely.
For a solo staker that combination — your own beacon node, your own explorer, your own alerting — is the setup that depends on nobody. It is more work than a browser bookmark, and it is the difference between monitoring your validator and asking someone else about it.