Asset Hub Kusama RPC Endpoints: Chain Settings, Faucet, and Debugging Tips

Asset Hub Kusama Decision Checklist

Before integrating with Asset Hub Kusama, evaluate these criteria to choose the right infrastructure:

What Is Asset Hub Kusama?

Asset Hub Kusama (formerly known as Statemine) is a common-good parachain on the Kusama network. It provides a low-cost environment for creating and managing digital assets—both fungible tokens and NFTs. It also serves as the native KSM transfer layer, enabling fast and cheap transactions compared to the Relay Chain.

Key features:

• Asset creation and management via the assets pallet.
• XCM (Cross-Consensus Message) support for cross-chain transfers.
• Smart contract support (EVM-compatible) via pallet-evm.
• Low transaction fees compared to the Relay Chain.

Chain Settings for Asset Hub Kusama

When connecting to Asset Hub Kusama, use these chain-specific parameters:

• Network name: Kusama Asset Hub
• Chain ID: 420420418 (EVM)
• Currency symbol: KSM
• Block explorer: https://assethub-kusama.subscan.io
• RPC URL (public): See endpoints below.
• WebSocket URL: See endpoints below.

Note: The EVM chain ID is used when interacting via Ethereum-compatible JSON-RPC. For Substrate-native calls, use the Substrate RPC methods.

RPC Endpoints for Asset Hub Kusama

You can connect to Asset Hub Kusama using public or dedicated RPC endpoints. Public endpoints are suitable for development and low-traffic use, while dedicated nodes are recommended for production applications.

Public Endpoints (use with caution)

• HTTP: https://rpc.assethub-kusama.subscan.io
• WebSocket: wss://rpc.assethub-kusama.subscan.io/ws

These are rate-limited and not guaranteed to be always available. For reliable access, consider a managed RPC provider.

Using OnFinality for Dedicated Nodes

OnFinality provides dedicated and shared RPC endpoints for Asset Hub Kusama with archive and trace support. You can spin up a dedicated node or use the shared API service with predictable pricing. See our supported networks for availability and RPC pricing for cost details.

To get started with OnFinality:

1. Sign up at OnFinality and create an API key.
2. Select "Kusama Asset Hub" from the network list.
3. Choose between shared or dedicated endpoints.
4. Use the provided HTTP and WebSocket URLs in your application.

Connecting via curl

Test a basic JSON-RPC call to Asset Hub Kusama:

curl -H "Content-Type: application/json" -d '{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "chain_getHeader",
  "params": []
}' https://rpc.assethub-kusama.subscan.io

For EVM queries (using chain ID 420420418):

curl -X POST \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' \
  https://rpc.assethub-kusama.subscan.io

Connecting via Polkadot.js

const { ApiPromise, WsProvider } = require('@polkadot/api');

const wsProvider = new WsProvider('wss://rpc.assethub-kusama.subscan.io/ws');
const api = await ApiPromise.create({ provider: wsProvider });

// Get chain info
const chain = await api.rpc.system.chain();
console.log('Connected to:', chain.toString());

Faucet and Test Tokens

Asset Hub Kusama does not have a dedicated testnet. Developers typically use the mainnet KSM for testing in development environments after acquiring tokens through an exchange or bridge. For low-risk testing, you can:

• Use a separate wallet with small amounts.
• Leverage the Asset Hub's low transaction fees (fractions of a cent).
• Use the Westend testnet for Polkadot ecosystem testing (note: Westend has its own Asset Hub).

Common Pitfalls and Troubleshooting

1. Incorrect Chain ID

When using EVM JSON-RPC, ensure you specify chain ID 420420418. Using the Relay Chain's chain ID will result in transaction failures.

2. Rate Limiting on Public Endpoints

Public endpoints often have strict rate limits. If you encounter HTTP 429 errors, switch to a dedicated provider like OnFinality or implement client-side throttling.

3. WebSocket Disconnections

Unstable WebSocket connections can disrupt real-time subscriptions. Use reconnection logic in your client or choose a provider with stable WebSocket infrastructure.

4. Archive Data Access

Some historical queries require archive node access. OnFinality's dedicated nodes support archive mode—ensure you select the archive feature when provisioning.

5. Cross-Chain Transfers (XCM)

Asset Hub Kusama supports XCM for sending assets to other parachains. Common issues include insufficient XCM deposit (ED) or incorrect destination. Always verify the destination parachain ID and asset ID.

Key Takeaways

• Asset Hub Kusama is the system parachain for assets on Kusama, offering low-cost asset creation and transfer.
• Chain ID for EVM is 420420418; use Substrate-native calls for pallet interactions.
• Public RPC endpoints are available but rate-limited; for production, consider dedicated nodes.
• OnFinality provides reliable dedicated and shared endpoints with archive, trace, and WebSocket support.
• Test with small KSM amounts; no testnet exists but mainnet fees are minimal.
• Monitor for rate limiting, WebSocket drops, and correct chain ID when troubleshooting.

Frequently Asked Questions

Q: What is the difference between Asset Hub Kusama and the Kusama Relay Chain?

A: Asset Hub Kusama is a parachain that handles asset logic and native KSM transfers, offloading work from the Relay Chain. The Relay Chain focuses on security, consensus, and cross-chain message routing.

Q: Can I deploy EVM smart contracts on Asset Hub Kusama?

A: Yes, Asset Hub Kusama includes pallet-evm, enabling deployment of Solidity smart contracts. The EVM chain ID is 420420418.

Q: How do I get KSM for testing?

A: Obtain KSM from an exchange and transfer it to your Asset Hub Kusama address. The fees are very low, so small amounts suffice for development.

Q: Does OnFinality support archive nodes for Asset Hub Kusama?

A: Yes, OnFinality offers archive node options. Check the network page for details.

Q: What tools can I use to interact with Asset Hub Kusama?

A: You can use Polkadot.js for Substrate calls, ethers.js or web3.js for EVM calls, and Subscan for block exploration.

Q: Is there a rate limit on OnFinality's shared endpoints?

A: Shared endpoints have fair-use limits. For predictable performance, choose a dedicated node plan. See pricing.

Q: How do I recover from a WebSocket disconnect?

A: Implement exponential backoff reconnection logic. Many libraries like Polkadot.js have built-in auto-reconnect options.