Logs & events20 CUFree key required

eth_getFilterChanges on Arbitrum Nova

Returns logs that arrived since the filter was last polled — the polling alternative to WebSocket subscriptions. Stateful; needs a free API key.

Returns only what's new since your last poll. Filters live in one node's memory and expire after a few idle minutes, so re-create on 'filter not found' and don't expect one to survive a node failover.

Arbitrum Nova endpoint (keyed — free)

https://rpc.nodeflare.app/nova/v1/YOUR_KEY

Method

eth_getFilterChanges

Cost

20 CU

Chain ID

42170

Block time

on-demand (min ~250 ms)

Finality

<1 s sequencer · L1-final ~13 min

Logs & events on Arbitrum Nova

Because blocks are on-demand, block-range windows map poorly to time windows — anchor ranges on timestamps via eth_getBlockByNumber probing. 75 CU per getLogs call.

Parameters

[filterId]

cURL

curl https://rpc.nodeflare.app/nova/v1/YOUR_KEY \
  -X POST \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","method":"eth_getFilterChanges","params":["0x0"],"id":1}'

ethers.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider(
  'https://rpc.nodeflare.app/nova/v1/YOUR_KEY'
);

const result = await provider.send('eth_getFilterChanges', ["0x0"]);

Try it live

Runs the example above against the public Arbitrum Nova endpoint — straight from your browser.

eth_getFilterChanges on Arbitrum Nova — FAQ

How do I call eth_getFilterChanges on Arbitrum Nova?

POST a JSON-RPC 2.0 request with "method": "eth_getFilterChanges" to NodeFlare's Arbitrum Nova endpoint at https://rpc.nodeflare.app/nova/v1/YOUR_KEY. This method requires a free API key — it is not available on the public endpoint.

What does eth_getFilterChanges cost on the free tier?

eth_getFilterChanges is weighted at 20 compute units per call. The free tier includes 2,000,000 CU/month, so that is roughly 100,000 eth_getFilterChanges calls per month — no credit card.

Is eth_getFilterChanges available on the public Arbitrum Nova endpoint?

No. eth_getFilterChanges is a heavy method and requires a free API key. The public no-key endpoint serves standard read methods; create a free key to unlock eth_getFilterChanges, eth_getLogs, trace_* and debug_*.

Anything Arbitrum Nova-specific to know when using eth_getFilterChanges?

Because blocks are on-demand, block-range windows map poorly to time windows — anchor ranges on timestamps via eth_getBlockByNumber probing. 75 CU per getLogs call.

Call eth_getFilterChanges on Arbitrum Nova with a free key

2,000,000 compute units/month, heavy methods unlocked, every chain included. No credit card.

Get your free API key →