What is the Arbitrum One mainnet RPC URL?

Arbitrum One's listed primary public RPC URL is https://arb1.arbitrum.io/rpc.

What is Arbitrum One's chain ID?

Arbitrum One's listed chain ID is 42161.

What block explorer does Arbitrum One use?

Arbitrum One's listed block explorer is https://arbiscan.io.

What gas token does Arbitrum One use?

Arbitrum One's listed gas token is ETH.

Chain profile

Arbitrum One chain ID 42161, RPC URL, and explorer

Reviewed June 10, 2026 Source monitor Jun 10, 2026

Source links checked June 10, 2026. Arbitrum One mainnet uses chain ID 42161 / 0xa4b1, RPC URL https://arb1.arbitrum.io/rpc, explorer https://arbiscan.io, and ETH as the gas token. Main.net keeps these fields together with official docs and source links for setup checks.

Answer first

Arbitrum chain ID answer

Arbitrum One mainnet uses chain ID 42161 / 0xa4b1, RPC URL https://arb1.arbitrum.io/rpc, explorer https://arbiscan.io, and ETH as the gas token. Main.net lists source links and copy-ready config fields without ranking RPC providers.

Chain ID: 42161 / 0xa4b1
RPC URL: https://arb1.arbitrum.io/rpc
Explorer: https://arbiscan.io
Gas token: ETH
Source docs: Arbitrum docs

Copy Arbitrum One config Open Arbitrum One guide Explorer directory Gas token directory

Exact setup guide

Arbitrum One chain ID and RPC guide

Use this source-cited guide when the search intent is specifically chain ID, RPC URL, explorer, gas token, or wallet config for Arbitrum One. It keeps the copied fields, official/source docs, and setup cautions together in one focused reference.

Open Arbitrum One chain ID and RPC guide Chain ID list Mainnet RPC list

Chain ID 42161 / 0xa4b1

RPC URL https://arb1.arbitrum.io/rpc

Explorer https://arbiscan.io

Gas token ETH

Verification Verified metadata

Manual review June 10, 2026

Source monitor Jun 10, 2026

Verification record

Manual metadata review and automated evidence checks are tracked separately. This is not a live uptime, latency, or production reliability monitor.

Manual metadata review: June 10, 2026
Verification status: Verified metadata
Verification run: source-monitoring-2026-06-10
Verification tool: source-monitoring-refresh
Source set: Arbitrum docs
Manual review cadence: monthly; after July 10, 2026
Latest recorded chain ID probe: eth_chainId matched expected 0xa4b1 ; observed 0xa4b1 on Jun 10, 2026

Methodology Report a correction

Glossary Chain ID How wallet and RPC software identify a mainnet network. Glossary RPC endpoint What an RPC URL does and why public endpoints can be rate-limited. Glossary Mainnet The production network context for reviewed chain settings. Gas token ETH gas token Other reviewed mainnet rows that use ETH for gas. Guide Arbitrum One chain ID and RPC guide Arbitrum-specific chain ID, RPC URL, explorer, gas token, and source links.

Monitoring evidence

These checks are review signals only. They are not uptime, latency, privacy, or production reliability claims.

Snapshot generated: Jun 10, 2026
Source checks: 1 sources checked
Source changes: 1 records since the previous committed source hash artifact
Source fetch failures: 0
eth_chainId probe: matched expected 0xa4b1
Last source check: Jun 10, 2026

View monitoring snapshots or source change history.

Network endpoints

Primary public RPC: https://arb1.arbitrum.io/rpc
Explorer: https://arbiscan.io
Official/source documentation: Arbitrum docs
Chain type: Optimistic L2 mainnet
Chain ID hex: 0xa4b1
Manual review cadence: monthly; next review after July 10, 2026

Arbitrum One common questions

What is the Arbitrum One mainnet RPC URL?: Arbitrum One's listed primary public RPC URL is https://arb1.arbitrum.io/rpc.
What is Arbitrum One's chain ID?: Arbitrum One's listed chain ID is 42161.
What block explorer does Arbitrum One use?: Arbitrum One's listed block explorer is https://arbiscan.io.
What gas token does Arbitrum One use?: Arbitrum One's listed gas token is ETH.

Copy-ready config

Neutral app configuration built from the verified fields above. Copy buttons only place text on your clipboard; they do not connect a wallet, request permissions, or rank RPC providers.

Chain ID decimal 42161

Chain ID hex 0xa4b1

RPC URL https://arb1.arbitrum.io/rpc

Explorer URL https://arbiscan.io

EIP-3085-shaped JSON

Rendered as text for manual review before use.

{
  "chainId": "0xa4b1",
  "chainName": "Arbitrum One",
  "nativeCurrency": {
    "name": "ETH",
    "symbol": "ETH",
    "decimals": 18
  },
  "rpcUrls": [
    "https://arb1.arbitrum.io/rpc"
  ],
  "blockExplorerUrls": [
    "https://arbiscan.io"
  ]
}

Developer snippets

Static examples generated from reviewed Main.net fields. These snippets are for manual configuration review and read-only RPC checks; they do not connect wallets, create signers, submit writes, or rank providers.

viem chain definition

Read-only snippet generated from reviewed Main.net fields. Review official sources before production use.

import { defineChain } from 'viem'

export const arbitrumOneMainnet = defineChain({
  id: 42161,
  name: "Arbitrum One",
  nativeCurrency: {
    name: "ETH",
    symbol: "ETH",
    decimals: 18,
  },
  rpcUrls: {
    default: { http: ["https://arb1.arbitrum.io/rpc"] },
    public: { http: ["https://arb1.arbitrum.io/rpc"] },
  },
  blockExplorers: {
    default: {
      name: "arbiscan.io",
      url: "https://arbiscan.io",
    },
  },
})

wagmi read-only config

Read-only transport example generated from reviewed fields. It does not include account adapters or transaction actions.

import { createConfig, http } from 'wagmi'
import { arbitrumOneMainnet } from './arbitrum-one'

export const config = createConfig({
  chains: [arbitrumOneMainnet],
  transports: {
    [arbitrumOneMainnet.id]: http("https://arb1.arbitrum.io/rpc"),
  },
})

ethers read-only provider

Read-only JsonRpcProvider example generated from reviewed fields. It does not create a signer.

import { JsonRpcProvider } from 'ethers'

export const provider = new JsonRpcProvider("https://arb1.arbitrum.io/rpc", {
  chainId: 42161,
  name: "arbitrum-one",
})

const network = await provider.getNetwork()
console.log(network.chainId)

bash

curl eth_chainId check

Minimal JSON-RPC identity check. This verifies the endpoint-reported chain ID only, not uptime or production suitability.

curl -s -X POST \
  -H 'content-type: application/json' \
  --data '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}' \
  https://arb1.arbitrum.io/rpc

# Expected chain ID: 42161 / 0xa4b1

Developer signals

External dashboards a developer may inspect before choosing where to deploy. Main.net links to these references but does not collect the metric values, normalize methodologies, rank chains, or recommend deployments.

activity growthepie chain metrics External activity, cost, throughput, stablecoin, and ecosystem metrics where this chain is covered. liquidity DeFiLlama chain page External TVL, stablecoin, volume, fee, and protocol coverage where this chain is covered. risk L2BEAT project page External L2 risk, value secured, activity, data availability, and trust-assumption research where this chain is covered. explorer Arbitrum One explorer Explorer-hosted blocks, transactions, contracts, token transfers, and verification tools from the listed explorer.

Main.net links to external developer-signal dashboards but does not collect, normalize, rank, or republish their metric values in this version.
External metrics can use different methodologies and update schedules. Check the linked provider documentation before comparing chains.
These links are not recommendations, rankings, investment advice, or claims that a chain is suitable for a specific application.

Source links

Arbitrum RPC endpoints

Safety note

Compare bridge routes, withdrawal timing, and finality assumptions before moving large balances across rollups.

Main.net is an independent reference site. It does not operate this chain, custody assets, execute transactions, or provide investment advice.

Report a correction

If this page has stale RPC, explorer, chain ID, or source information, open a public correction issue with a source link so the dataset can be reviewed.

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