Blocks2 CU

eth_getBlockByHash on Arbitrum One

Fetches a full block by its hash. Identical payload to eth_getBlockByNumber but keyed on the 32-byte block hash.

Use it when you already hold a hash (from a log or a parent-hash walk) and need reorg-safe lookup: unlike a block number, a hash pins one specific block even across a reorg.

Arbitrum One endpoint (public — no key)

https://rpc.nodeflare.app/arb/public

Method

eth_getBlockByHash

Cost

2 CU

Chain ID

42161

Block time

~250 ms

Finality

<1 s sequencer · L1-final ~13 min

Blocks on Arbitrum One

Arbitrum produces blocks on demand, as fast as ~250 ms apart — the fastest cadence of any chain we serve. block.number is the L2 block; a single day can span hundreds of thousands of blocks.

Parameters

[blockHash, fullTransactions:boolean]

cURL

curl https://rpc.nodeflare.app/arb/public \
  -X POST \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","method":"eth_getBlockByHash","params":["0x0000000000000000000000000000000000000000000000000000000000000000", false],"id":1}'

ethers.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider(
  'https://rpc.nodeflare.app/arb/public'
);

const result = await provider.send('eth_getBlockByHash', ["0x0000000000000000000000000000000000000000000000000000000000000000", false]);

Try it live

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

eth_getBlockByHash on Arbitrum One — FAQ

How do I call eth_getBlockByHash on Arbitrum One?

POST a JSON-RPC 2.0 request with "method": "eth_getBlockByHash" to NodeFlare's Arbitrum One endpoint at https://rpc.nodeflare.app/arb/public. No API key is required for the public endpoint.

What does eth_getBlockByHash cost on the free tier?

eth_getBlockByHash is weighted at 2 compute units per call. The free tier includes 2,000,000 CU/month, so that is roughly 1,000,000 eth_getBlockByHash calls per month — no credit card.

Is eth_getBlockByHash available on the public Arbitrum One endpoint?

Yes. eth_getBlockByHash works on the public Arbitrum One endpoint (https://rpc.nodeflare.app/arb/public) with no API key, rate-limited per IP. A free key adds higher limits and a dedicated path.

Anything Arbitrum One-specific to know when using eth_getBlockByHash?

Arbitrum produces blocks on demand, as fast as ~250 ms apart — the fastest cadence of any chain we serve. block.number is the L2 block; a single day can span hundreds of thousands of blocks.

Call eth_getBlockByHash on Arbitrum One with a free key

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

Get your free API key →