eth_blockNumber

eth_blockNumber returns the height of the most recently accepted block on Polygon PoS — the latest block sealed by a Bor producer. Because Polygon mines a new block roughly every 2 seconds, this value moves fast and is the simplest way to confirm your node is keeping up with the head of the chain. Gas on Polygon is paid in MATIC, but this call costs nothing on-chain: it is a pure read. Send it to https://polygon.therpc.io/YOUR_API_KEY (chain ID 137, 0x89) and you get back the current block height as a hex string.

Use cases

• Heartbeat probe: the cheapest call to confirm polygon.therpc.io is up and synced to the Polygon head.
• Establish the current Bor block height before paginating eth_getLogs over a historical range.
• Drive a "wait for N confirmations" loop in a deployment script — at ~2s blocks, a dozen confirmations clears in well under a minute.
• Compare the head against a target height to judge how close a transaction is to a Heimdall checkpoint anchored on Ethereum L1.

Parameters

Diese Methode erwartet keine Parameter. Übergib ein leeres Array [].

Response

Example request

1curl https://polygon.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_blockNumber",
7    "params": [],
8    "id": 1
9  }'

Try it live in the Polygon playground.

Errors & troubleshooting

Common pitfalls

• The result is a hex string like 0x3a1f2c, not a number — run parseInt(value, 16) or BigInt(value) before any arithmetic.
• The head is cached briefly; two calls milliseconds apart can return the same height even though Polygon advances every ~2 seconds. Poll on a short interval rather than in a tight loop.
• This is the Polygon PoS (Bor) block height, not the Ethereum L1 checkpoint height. A block being at the head here does not mean its checkpoint has been committed to Ethereum yet.

Supported networks

• Mainnet — Chain ID: 137
• Amoy — Chain ID: 80002

See also

• eth_getBlockByNumber
• eth_getBlockByHash
• eth_syncing
• eth_chainId

1curl https://polygon.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_blockNumber","params":[]}'