Blockchain RPC node monitoring
An RPC endpoint that answers but has stopped advancing is worse than one that is down — your app keeps reading stale state and never errors. PingDog calls the chain on your schedule and catches exactly that.
What PingDog checks
- A valid JSON-RPC response to eth_blockNumber
- The block height is a well-formed hex number
- The head is not stale — the block advances between checks, not frozen
Node operators and dapp teams live and die by RPC health, and "up" is not enough. A node can respond to every request while quietly stuck behind the tip of the chain — a syncing pause, a peer partition, a bad upgrade. Reads succeed, but against a frozen view of the world.
PingDog treats staleness as a first-class failure: it compares the block height across checks and flags a head that has stopped moving, so a stuck node pages you instead of silently corrupting your app's view of state. This is one of the checks built specifically for the crypto-infrastructure audience PingDog serves.
Anonymous, pay-per-check
Like everything on PingDog, this check needs no account: your key is the account, you pay once at $0.0005 per delivered check in USDC on Base, and nothing renews. A real free tier runs up to 3 monitors at a 5 minutes interval with no payment at all. See how pricing works.
Frequently asked
What counts as a stale RPC node?
One whose reported block height does not advance between consecutive checks. PingDog remembers the previous height and flags a head that has stopped moving, even when the endpoint is still answering requests.
Which chains work?
Any Ethereum-compatible endpoint that answers eth_blockNumber over JSON-RPC — mainnets, L2s, testnets and private chains alike.