What is the Harmony mainnet RPC URL?

Harmony's listed primary public RPC URL is https://api.harmony.one.

What is Harmony's chain ID?

Harmony's listed chain ID is 1666600000.

What block explorer does Harmony use?

Harmony's listed block explorer is https://explorer.harmony.one.

What gas token does Harmony use?

Harmony's listed gas token is ONE.

Chain profile

Harmony chain ID 1666600000 and mainnet RPC URL

Source snapshotJuly 4, 2026

Source evidence snapshot July 4, 2026. Harmony documentation lists Harmony Mainnet Shard 0 with RPC URL, chain ID 1666600000, ONE as currency symbol, and the Harmony explorer.

Quick settings

Harmony RPC status and chain ID answer

Harmony mainnet uses chain ID 1666600000 / 0x63564c40, RPC URL https://api.harmony.one, explorer https://explorer.harmony.one, and ONE as the gas token. Use the latest source check and linked docs to verify the fields before adding the network to a wallet, script, or app.

Chain ID: 1666600000 / 0x63564c40
RPC URL: https://api.harmony.one
Explorer: https://explorer.harmony.one
Gas token: ONE
Source docs: Harmony docs
Latest check: Jul 20, 2026
Source snapshot: July 4, 2026
Config path: wallet_addEthereumChain JSON

Copy Harmony config Open source docs Explorer directory Gas token directory

Good fit when you need:

the Harmony chain ID, RPC URL, explorer, and gas token in one place;
source documentation links beside the copied setup fields;
manual wallet config fields without connecting a wallet or choosing an RPC provider.

Before you paste these fields:

compare the chain ID against the source link on this page;
open the explorer once and confirm it matches the network you expect;
use the public RPC for setup checks, then choose monitored infrastructure for production traffic.

Chain ID1666600000 / 0x63564c40

RPC URLhttps://api.harmony.one

Explorerhttps://explorer.harmony.one

Gas tokenONE

VerificationVerified metadata

Source snapshotJuly 4, 2026

Evidence snapshotJul 20, 2026

Verification record

Automated source snapshots and recorded probe evidence are tracked separately. The source snapshot timestamp is not a manual review date. This is not a live uptime, latency, or production reliability monitor. If a recorded public RPC probe fails, verify the source links and current endpoint availability before changing production configuration.

Automated source snapshot: July 4, 2026
Verification status: Verified metadata
Source snapshot run: source-monitoring-2026-07-04
Source snapshot tool: source-monitoring-refresh
Source set: Harmony docs
Latest recorded chain ID probe: eth_chainId matched expected 0x63564c40; observed 0x63564c40 on Jul 20, 2026

Methodology Report a correction

Harmony wallet-add fields

Wallet directory sites often expose a connect button. Main.net keeps the same MetaMask and EIP-3085 setup fields as text so developers can compare them with official/source docs before calling wallet_addEthereumChain.

chainId: 0x63564c40 (1666600000)
chainName: Harmony
nativeCurrency: ONE; name ONE, symbol ONE, decimals 18
rpcUrls: https://api.harmony.one
blockExplorerUrls: https://explorer.harmony.one

GlossaryChain IDHow wallet and RPC software identify a mainnet network.GlossaryRPC endpointWhat an RPC URL does and why public endpoints can be rate-limited.GlossaryMainnetThe production network context for these chain settings.Gas tokenONE gas tokenOther mainnet rows that use ONE for gas.Network categoryEVM mainnetsCompare Harmony with related evm mainnets by chain ID, RPC URL, explorer, and source links.Network categoryL1 mainnetsCompare Harmony with related l1 mainnets by chain ID, RPC URL, explorer, and source links.GuideChain ID listChain 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. A source fetch failure or eth_chainId failure can mean a source page or public RPC endpoint was unavailable, changed, or rate-limited during a check. Re-open source links and test current RPC availability before relying on a public endpoint.

Snapshot generated: Jul 20, 2026
Source checks: 2 sources checked
Source changes: 0 changes since the previous source hash snapshot
Source fetch failures: 0
eth_chainId probe: matched expected 0x63564c40
Per-source check timing: Included in the monitoring snapshot, not represented as a manual review or page freshness date

View monitoring snapshots orsource change history.

Network endpoints

Primary public RPC: https://api.harmony.one
Explorer: https://explorer.harmony.one
Official/source documentation: Harmony docs
Chain type: EVM L1 mainnet
Chain ID hex: 0x63564c40
Source snapshot provenance: source-monitoring-2026-07-04 via source-monitoring-refresh

Harmony common questions

What is the Harmony mainnet RPC URL?: Harmony's listed primary public RPC URL is https://api.harmony.one.
What is Harmony's chain ID?: Harmony's listed chain ID is 1666600000.
What block explorer does Harmony use?: Harmony's listed block explorer is https://explorer.harmony.one.
What gas token does Harmony use?: Harmony's listed gas token is ONE.

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 decimal1666600000

Chain ID hex0x63564c40

RPC URLhttps://api.harmony.one

Explorer URLhttps://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 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 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",
    },
  },
})

wagmi read-only config

Read-only transport example generated from Main.net 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"),
  },
})

ethers read-only provider

Read-only JsonRpcProvider example generated from Main.net 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.

explorerHarmony explorerExplorer-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

Add Harmony to MetaMask Harmony 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 it can be checked.

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