> For the complete documentation index, see [llms.txt](https://docs.megaeth.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.megaeth.com/developer-docs/rpc/reference/eth_getcodebyhash.md).

# eth\_getCodeByHash

## Summary

Returns runtime bytecode for a given code hash.

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

## Parameters

**`codeHash`** Hash32 **REQUIRED**

Target runtime code hash.

## Result

**`result`** Data

Runtime bytecode; `0x` when no bytecode is stored for that hash.

## Comparison with Ethereum Standard JSON-RPC

### Ethereum Standard

`eth_getCodeByHash` is not part of the core Ethereum execution JSON-RPC API. It is an implementation-specific extension.

### MegaETH Node Behavior

MegaETH adds a direct code-hash lookup that returns the stored runtime bytecode. An unknown code hash produces empty bytecode rather than an account lookup.

### MegaETH Public Gateway

The public gateway exposes this MegaETH extension and caches successful immutable lookups for 30 minutes.

## Errors

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

No method-specific errors were observed.

| Code     | Scope            | Message             | When it happens                                             |
| -------- | ---------------- | ------------------- | ----------------------------------------------------------- |
| `-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](/developer-docs/rpc/error-codes.md).

## Examples

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

Capture date: July 24, 2026

Outcome: success

```json
{
  "jsonrpc": "2.0",
  "id": 43,
  "method": "eth_getCodeByHash",
  "params": [
    "0xfa8c9db6c6cab7108dea276f4cd09d575674eb0852c0fa3187e59e98ef977998"
  ]
}
```

```json
{
  "jsonrpc": "2.0",
  "id": 43,
  "result": "0x6080604052\u2026"
}
```

## Sources

* Spec: EIP-1474 for JSON-RPC framing and error conventions; this method is an extension or legacy compatibility method.
* Code: `git@github.com:megaeth-labs/mega-reth.git @ ab60376631228edab3a6df180f295280bad26e93: crates/megaeth/rpc/src/eth/ext.rs`
* Code: `git@github.com:megaeth-labs/mega-rpc.git @ 06aa35aa95d569c227cc25d2aa12834eb0458aa0: workers/src/spec/methods.ts`
* Probe: MegaETH Mainnet public endpoint, July 24, 2026


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