---
title: "eth_getLogs"
description: "Returns event logs on Base matching a filter object; pair with pending on Flashblocks to query logs from pre-confirmed transactions."
source: https://basehub.org/api-reference/eth/eth_getlogs/
---
import { Aside, Tabs, TabItem } from '@astrojs/starlight/components';

Returns an array of all logs matching a filter object. The primary tool for indexing on-chain events.

<Aside type="caution">
Queries that span large block ranges or high-activity contracts can time out or be rejected. Keep `fromBlock`-to-`toBlock` ranges under 2,000 blocks for reliable results. Node providers may enforce their own limits.
</Aside>

<Aside type="tip">
**Flashblocks:** set `"fromBlock": "pending"` and `"toBlock": "pending"` against `https://mainnet-preconf.base.org` to query logs from pre-confirmed transactions, refreshed every ~200ms. For a real-time stream, consider the [`pendingLogs`](/api-reference/flashblocks/pendinglogs/) WebSocket subscription instead.
</Aside>

## Parameters

### `filter` (object, required)

Filter options. At least one criterion should be provided.

| Field | Type | Description |
| --- | --- | --- |
| `fromBlock` | string | Start of the block range. Block number in hex or a block tag. Pass `"pending"` on a Flashblocks endpoint to include pre-confirmed logs. Defaults to `"latest"`. |
| `toBlock` | string | End of the block range. Block number in hex or a block tag. Defaults to `"latest"`. |
| `address` | string \| array | A contract address or array of addresses to filter by. Optional. |
| `topics` | array | Array of 32-byte topic filters. Each position can be `null` (match any), a single topic hex string, or an array of hex strings (match any in the array). Position 0 is typically the `keccak256` hash of the event signature. Optional. |
| `blockHash` | string | Restricts logs to the block with this hash. When supplied, `fromBlock` and `toBlock` are ignored. Optional. |

## Returns

`result` (array of log objects):

| Field | Type | Description |
| --- | --- | --- |
| `address` | string | 20-byte address of the contract that emitted the log. |
| `topics` | array | Array of 0–4 indexed 32-byte topics. Topic 0 is typically the event signature hash. |
| `data` | string | ABI-encoded non-indexed event parameters. |
| `blockNumber` | string | Block number in which this log was emitted (hex). |
| `transactionHash` | string | 32-byte hash of the transaction that emitted this log. |
| `transactionIndex` | string | Index of the transaction in the block (hex). |
| `blockHash` | string | 32-byte hash of the block. |
| `logIndex` | string | The log's index position within the block (hex). |
| `removed` | boolean | `true` if the log was removed due to a chain reorganization. |

## Example

### Request

<Tabs>
  <TabItem label="Standard (block range)">

```bash
curl https://mainnet.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [{
      "fromBlock": "0x12ced00",
      "toBlock": "0x12ced28",
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]
    }],
    "id": 1
  }'
```

  </TabItem>
  <TabItem label="Flashblocks (pending, ~200ms)">

```bash
curl https://mainnet-preconf.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [{
      "fromBlock": "pending",
      "toBlock": "pending",
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]
    }],
    "id": 1
  }'
```

  </TabItem>
</Tabs>

### Response

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    {
      "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
        "0x000000000000000000000000d3cda913deb6f4967b2ef66ae97de114a83bcc01",
        "0x0000000000000000000000004200000000000000000000000000000000000006"
      ],
      "data": "0x0000000000000000000000000000000000000000000000000000000005f5e100",
      "blockNumber": "0x12ced28",
      "transactionHash": "0xb903239f8543d04b5dc1ba6579132b143087c68db1b2168786408fcbce568238",
      "transactionIndex": "0x0",
      "blockHash": "0x3a4e8c5d7f2b1a6e9d0c4f8b3e7a2d5c8f1b4e7a0d3c6f9b2e5a8d1c4f7b0e3",
      "logIndex": "0x0",
      "removed": false
    }
  ]
}
```