eth_maxPriorityFeePerGas

eth_maxPriorityFeePerGas returns the node's suggested priority fee, the tip in wei that a sender adds on top of the burned base fee to get a transaction picked up by the next Ethereum validator. Since the London upgrade brought EIP-1559, a type-2 transaction sets maxFeePerGas and maxPriorityFeePerGas separately; this call gives you a reasonable number for the second of those. The node derives it heuristically from recent block history rather than reading a fixed price. Query it at https://ethereum.therpc.io/YOUR_API_KEY on chain ID 1 with no parameters, and you get a hex-encoded wei value back, denominated in ETH's smallest unit.

Use cases

Fill in the maxPriorityFeePerGas field of an EIP-1559 (type-2) transaction before signing, so your tip tracks current Ethereum demand instead of a stale constant.
Seed a wallet's fee picker with a sensible default tip, then let the user nudge it up for faster inclusion during congestion.

Parameters

This method takes no parameters. Pass an empty array [].

Response

Type	Description
string	Hex-encoded priority fee in wei. This is the node's heuristic — typically derived from recent block history.

Example request

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

Try it live in the Ethereum playground.

Errors & troubleshooting

Code	Message	Cause
`-32000`	`method not supported`	The connected network does not implement EIP-1559 and does not support this method.

Common pitfalls

The value is a heuristic, not a protocol constant. Two different clients (geth versus erigon, say) can return slightly different tips for the same block, so treat it as a starting estimate.
This is an EIP-1559 method. On a chain or fork without the London fee market it can error or hand back a meaningless number; in those cases fall back to eth_gasPrice and a legacy transaction.
When you need precision, for example a tip pegged to a specific percentile of recent blocks, build it from eth_feeHistory with explicit reward percentiles rather than this single suggested value.

Supported networks

Mainnet — Chain ID: 1
Sepolia — Chain ID: 11155111