> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.
## Submitting Feedback
If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:
POST https://docs.chainstack.com/feedback
```json
{
"path": "/reference/hyperliquid-evm-eth-get-uncle-by-block-number-and-index",
"feedback": "Description of the issue"
}
```
Only submit feedback when you have something specific and actionable to report.
# eth_getUncleByBlockNumberAndIndex | Hyperliquid EVM
> Returns information about an uncle block by the block number and uncle index position. Uncle blocks are valid blocks that were not included in the main chain but are referenced by the main chain blocks.
This method is available on Chainstack. Not all Hyperliquid methods are available on Chainstack, as the open-source node implementation does not support them yet — see [Hyperliquid methods](/docs/hyperliquid-methods) for the full availability breakdown.
The `eth_getUncleByBlockNumberAndIndex` JSON-RPC method returns information about an uncle block by block number and uncle index position. Uncle blocks are valid blocks that were not included in the main chain but are referenced by the main chain blocks for network security.
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## Parameters
1. **block\_number** (string) — The block number as a hexadecimal string, or one of the string tags: "latest", "earliest", or "pending"
2. **uncle\_index** (string) — The uncle index position as a hexadecimal string (e.g., "0x0" for the first uncle)
## Response
The method returns uncle block information or `null` if no uncle exists at the specified index.
### Response structure
**Uncle block information:**
* Returns uncle block object with header information if found
* Returns `null` if no uncle exists at the specified index
* Uncle blocks contain header information but no transaction data
### Block number tags
**Available tags:**
* `"latest"` — The most recent block in the chain
* `"earliest"` — The genesis block (block 0)
* `"pending"` — The pending state/transactions
**Hexadecimal format:**
* Block numbers can be specified as hexadecimal strings with "0x" prefix
* Example: "0x1b4" represents block 436 in decimal
## Usage example
### Basic implementation
```javascript theme={"system"}
// Get uncle block by number and index
const getUncleByBlockNumberAndIndex = async (blockNumber, uncleIndex) => {
const response = await fetch('https://hyperliquid-mainnet.core.chainstack.com/YOUR_ENDPOINT/evm', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
},
body: JSON.stringify({
jsonrpc: '2.0',
method: 'eth_getUncleByBlockNumberAndIndex',
params: [blockNumber, uncleIndex],
id: 1
})
});
const data = await response.json();
return data.result;
};
// Monitor latest block for uncles
const monitorLatestBlockUncles = async () => {
const uncles = [];
let index = 0;
while (true) {
const uncle = await getUncleByBlockNumberAndIndex(
'latest',
`0x${index.toString(16)}`
);
if (uncle === null) {
break;
}
uncles.push(uncle);
index++;
}
return uncles;
};
// Check uncles in a specific block
const checkBlockUncles = async (blockNumber) => {
const result = {
blockNumber,
uncles: [],
uncleCount: 0
};
let index = 0;
while (true) {
const uncle = await getUncleByBlockNumberAndIndex(
blockNumber,
`0x${index.toString(16)}`
);
if (uncle === null) {
break;
}
result.uncles.push(uncle);
index++;
}
result.uncleCount = result.uncles.length;
return result;
};
// Usage
monitorLatestBlockUncles().then(uncles => {
console.log(`Latest block has ${uncles.length} uncles`);
});
checkBlockUncles('0x100').then(result => {
console.log(`Block ${result.blockNumber} has ${result.uncleCount} uncles`);
});
```
## Example request
```shell Shell theme={"system"}
curl -X POST \
-H "Content-Type: application/json" \
-d '{
"jsonrpc": "2.0",
"method": "eth_getUncleByBlockNumberAndIndex",
"params": [
"latest",
"0x0"
],
"id": 1
}' \
https://hyperliquid-mainnet.core.chainstack.com/4f8d8f4040bdacd1577bff8058438274/evm
```
## Use cases
The `eth_getUncleByBlockNumberAndIndex` method is useful for applications that need to:
* **Real-time monitoring**: Monitor uncle blocks in the latest blocks
* **Mining analytics**: Analyze mining performance and uncle rates
* **Network health monitoring**: Track network consensus and chain quality
* **Block explorer development**: Build block explorers with uncle block support
* **Mining pool operations**: Monitor mining pool uncle block statistics
* **Blockchain research**: Study consensus mechanisms and network behavior
* **Network statistics**: Generate uncle block statistics and trends
* **Performance analysis**: Analyze blockchain performance and efficiency
* **Educational platforms**: Create educational content about blockchain consensus
* **Mining reward calculation**: Calculate mining rewards including uncle rewards
* **Chain analysis tools**: Build tools for detailed blockchain analysis
* **Monitoring dashboards**: Create dashboards for blockchain metrics
* **Academic research**: Support research on blockchain consensus algorithms
* **Network optimization**: Optimize network parameters based on uncle patterns
* **Historical data analysis**: Analyze uncle block trends over time
This method provides efficient access to uncle block information using block numbers, enabling comprehensive blockchain monitoring and analysis on the Hyperliquid EVM platform.
## OpenAPI
````yaml /openapi/hyperliquid_node_api/evm_eth_get_uncle_by_block_number_and_index.json post /evm
openapi: 3.0.0
info:
title: Hyperliquid EVM API - eth_getUncleByBlockNumberAndIndex
version: 1.0.0
servers:
- url: >-
https://hyperliquid-mainnet.core.chainstack.com/4f8d8f4040bdacd1577bff8058438274
security: []
paths:
/evm:
post:
summary: eth_getUncleByBlockNumberAndIndex
description: >-
Returns information about an uncle block by the block number and uncle
index position. Uncle blocks are valid blocks that were not included in
the main chain but are referenced by the main chain blocks.
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- jsonrpc
- method
- params
- id
properties:
jsonrpc:
type: string
enum:
- '2.0'
default: '2.0'
description: JSON-RPC version
method:
type: string
enum:
- eth_getUncleByBlockNumberAndIndex
default: eth_getUncleByBlockNumberAndIndex
description: The RPC method name
params:
type: array
description: 'Parameters: [block_number, uncle_index]'
default:
- latest
- '0x0'
id:
type: integer
default: 1
description: Request identifier
example:
jsonrpc: '2.0'
method: eth_getUncleByBlockNumberAndIndex
params:
- latest
- '0x0'
id: 1
responses:
'200':
description: Successful response with uncle block information
content:
application/json:
schema:
type: object
properties:
jsonrpc:
type: string
description: JSON-RPC version
id:
type: integer
description: Request identifier
result:
type: object
description: Uncle block information or null if not found
nullable: true
example:
jsonrpc: '2.0'
id: 1
result: null
````