Main.net Mainnet intelligence

Chain profile

Harmony chain ID 1666600000 and mainnet RPC URL

Harmony documentation lists Harmony Mainnet Shard 0 with RPC URL, chain ID 1666600000, ONE as currency symbol, and the Harmony explorer.

Chain ID 1666600000 / 0x63564c40
Gas token ONE
Verification Verified metadata
Checked April 30, 2026

Verification record

This page is checked against cited public sources. It is not a live uptime, latency, or production reliability monitor.

Last checked
Verification status
Verified metadata
Verification run
manual-static-seed-2026-04-30
Verification tool
manual-source-review
Source set
Harmony docs
Next review
monthly; after May 30, 2026
Latest chain ID probe
eth_chainId matched expected 0x63564c40 ; observed 0x63564c40 at

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 ONE gas token Other reviewed mainnet rows that use ONE for gas. Guide Chain ID list Reviewed chain IDs, RPC URLs, explorers, and source links across Main.net.

Monitoring evidence

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

Source checks
2 sources checked
Source changes
0 records since the previous committed source hash artifact
Source fetch failures
0
eth_chainId probe
matched expected 0x63564c40
Last source check

View monitoring snapshots or source change history.

Network endpoints

Primary public RPC
https://api.harmony.one
Explorer
https://explorer.harmony.one
Source documentation
Harmony docs
Chain type
EVM L1 mainnet
Chain ID hex
0x63564c40
Review cadence
monthly; next review after May 30, 2026

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 1666600000
Chain ID hex 0x63564c40
RPC URL https://api.harmony.one
Explorer URL https://explorer.harmony.one
EIP-3085-shaped JSON

Rendered as text for manual review before use.

{
  "chainId": "0x63564c40",
  "chainName": "Harmony",
  "nativeCurrency": {
    "name": "ONE",
    "symbol": "ONE",
    "decimals": 18
  },
  "rpcUrls": [
    "https://api.harmony.one"
  ],
  "blockExplorerUrls": [
    "https://explorer.harmony.one"
  ]
}

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.

ts

viem chain definition

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

import { defineChain } from 'viem'

export const harmonyMainnet = defineChain({
  id: 1666600000,
  name: "Harmony",
  nativeCurrency: {
    name: "ONE",
    symbol: "ONE",
    decimals: 18,
  },
  rpcUrls: {
    default: { http: ["https://api.harmony.one"] },
    public: { http: ["https://api.harmony.one"] },
  },
  blockExplorers: {
    default: {
      name: "explorer.harmony.one",
      url: "https://explorer.harmony.one",
    },
  },
})
ts

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 { harmonyMainnet } from './harmony'

export const config = createConfig({
  chains: [harmonyMainnet],
  transports: {
    [harmonyMainnet.id]: http("https://api.harmony.one"),
  },
})
ts

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://api.harmony.one", {
  chainId: 1666600000,
  name: "harmony",
})

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://api.harmony.one

# Expected chain ID: 1666600000 / 0x63564c40

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.

explorer Harmony explorer Explorer-hosted blocks, transactions, contracts, token transfers, and verification tools from the listed explorer.

Source links

Add Harmony to MetaMaskHarmony network and faucets

Safety note

Harmony documentation distinguishes mainnet shards. Use Shard 0 settings for common wallet, exchange, and staking workflows unless a source requires another shard.

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.

Report Harmony data