eth_feeHistory

eth_feeHistory JSON-RPC reference for MegaETH.

Summary

Returns historical gas fee data for a range of blocks.

The public MegaETH endpoint supports this method. The standard, node, and gateway layers below identify behavior that differs from a generic Ethereum endpoint.

Parameters

blockCount Quantity REQUIRED

Number of blocks (1–256).

---

newestBlock string REQUIRED

Hex block number or tag: latest, safe, finalized, earliest, pending.

---

rewardPercentiles number[]

Monotonically increasing values from 0 to 100; omit to exclude reward from the result.

Result

• oldestBlock Quantity

  First block in the returned range.
• baseFeePerGas Quantity[]

  Base fee per block; length is blockCount + 1.
• gasUsedRatio number[]

  Gas utilization ratio per block.
• reward Quantity[][]

  Percentile reward values; present only when rewardPercentiles was provided.
• baseFeePerBlobGas Quantity[]

  Blob base fee per block when available.
• blobGasUsedRatio number[]

  Blob gas utilization ratio per block when available.

Comparison with Ethereum Standard JSON-RPC

Ethereum Standard

The canonical Ethereum method uses the parameter and result contract documented above, including the stated null, false, or zero-value semantics where applicable.

MegaETH Node Behavior

The node implements the standard fee-history shape. The public gateway does not forward this method to the node, so node-derived fee history must not be inferred from public results.

MegaETH Public Gateway

The gateway synthesizes this response locally instead of querying a node. It accepts 1 to 256 blocks and currently fills the response with a 1,000,000-wei base fee, 0.1 gas-used ratio, 1-wei blob base fee, zero blob utilization, and zero rewards. Treat these as gateway policy values, not measured historical blocks.

Errors

The | Scope | column distinguishes method failures from gateway policy errors.

Code	Scope	Message	When it happens
-32602	Request	Invalid params	Invalid request shape or blockCount outside the allowed range
-32005	Transport/policy	Rate limit exceeded	The caller exceeds the public gateway's simple read budget.
-32099	Transport/policy	Payload too large	The request body exceeds the 128 KiB public endpoint limit.

See also Error Codes.

Examples

Endpoint: https://mainnet.megaeth.com/rpc

Capture date: July 27, 2026

Outcome: success

{
  "jsonrpc": "2.0",
  "id": 66,
  "method": "eth_feeHistory",
  "params": ["0x2", "latest", [25, 75]]
}

{
  "jsonrpc": "2.0",
  "id": 66,
  "result": {
    "oldestBlock": "0xfffff",
    "baseFeePerGas": ["0xf4240", "0xf4240", "0xf4240"],
    "gasUsedRatio": [0.1, 0.1],
    "reward": [
      ["0x0", "0x0"],
      ["0x0", "0x0"]
    ],
    "baseFeePerBlobGas": ["0x1", "0x1", "0x1"],
    "blobGasUsedRatio": [0, 0]
  }
}

Sources

• Spec: [email protected]:ethereum/execution-apis.git @ d24f58b56dcd16ab0f0c70ec609bcc1c42750b51: src/eth/fee_market.yaml
• Code: [email protected]:megaeth-labs/mega-reth.git @ ab60376631228edab3a6df180f295280bad26e93: crates/rpc/rpc-eth-api/src/core.rs
• Code: [email protected]:megaeth-labs/mega-rpc.git @ 06aa35aa95d569c227cc25d2aa12834eb0458aa0: workers/src/processors/fee-history-processor.ts
• Probe: MegaETH Mainnet public endpoint, July 27, 2026