Offchain

Arbitrum One JSON-RPC

Public Ethereum-compatible JSON-RPC endpoint for Arbitrum One (chain id 42161 / 0xa4b1), the flagship Arbitrum layer-2 network. Supports the standard Ethereum JSON-RPC method set (eth_*, net_*, web3_*) plus Arbitrum-specific precompile methods over HTTPS POST.

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Documentation

📖
Documentation
https://docs.arbitrum.io/for-devs/dev-tools-and-resources/chain-info

Other Resources

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APIsJSON
https://raw.githubusercontent.com/api-evangelist/offchain/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: Arbitrum One JSON-RPC
description: Public Ethereum-compatible JSON-RPC endpoint for Arbitrum One (chain id 42161 / 0xa4b1),
  the flagship Arbitrum layer-2 network. Supports the standard Ethereum JSON-RPC method set (eth_*, net_*,
  web3_*) plus Arbitrum-specific precompile methods over HTTPS POST.
humanURL: https://docs.arbitrum.io/for-devs/dev-tools-and-resources/chain-info
baseURL: https://arb1.arbitrum.io/rpc
tags:
- Ethereum
- Layer 2
- JSON-RPC
- Blockchain
properties:
- type: Documentation
  url: https://docs.arbitrum.io/for-devs/dev-tools-and-resources/chain-info