Zhuoxin Sun

Posted on Jul 23 • Originally published at onfinality.io

BNB Smart Chain Testnet RPC Endpoints, Chain Settings & Faucet

#blockchain #devops #web3 #tutorial

BNB Smart Chain Testnet Decision Checklist

Before you start building on BNB Smart Chain Testnet, consider the following:

Criterion	What to check	Why it matters
Endpoint reliability	Does the provider offer a dedicated or shared endpoint?	Shared endpoints may have rate limits that affect testing.
WebSocket support	Does the endpoint support wss?	Required for real-time event listening (e.g., pending transactions, logs).
Faucet availability	Can you get tBNB easily?	Without test tokens, you cannot deploy contracts or send transactions.
Archive data	Do you need historical state?	Archive nodes are needed for certain queries like eth_getBalance at old blocks.
Chain ID	Is it 97 (0x61)?	Using the wrong chain ID will cause transaction rejections.
Explorer	Can you verify transactions?	Testnet BscScan helps debug failed transactions.

What Is BNB Smart Chain Testnet?

BNB Smart Chain Testnet (also called BSC Testnet) is a test environment that mirrors the BNB Smart Chain mainnet. It uses the same Proof of Staked Authority (PoSA) consensus and is fully EVM-compatible. Developers use it to deploy and test smart contracts, dApps, and infrastructure without risking real funds. The native token is tBNB, which has no monetary value and can be obtained from faucets.

Chain Configuration

To connect to BNB Smart Chain Testnet, use the following settings:

Network Name: BNB Smart Chain Testnet
RPC URL: See endpoints below
Chain ID: 97 (0x61)
Currency Symbol: tBNB
Block Explorer URL: https://testnet.bscscan.com

RPC Endpoints

Public Endpoints (Rate Limited)

These endpoints are provided by the BNB Chain team and various community providers. They are suitable for light testing but may have rate limits (e.g., 10,000 requests per 5 minutes).

https://data-seed-prebsc-1-s1.bnbchain.org:8545
https://data-seed-prebsc-2-s1.bnbchain.org:8545
https://bsc-testnet-rpc.publicnode.com
wss://bsc-testnet-rpc.publicnode.com

Managed Endpoints (Higher Reliability)

For more consistent performance, consider using a managed RPC provider like OnFinality. OnFinality offers dedicated and shared endpoints for BNB Smart Chain Testnet with higher rate limits, WebSocket support, and optional archive data.

https://bnb-testnet.api.onfinality.io/public
wss://bnb-testnet.api.onfinality.io/public

To get a private endpoint with dedicated resources, sign up at OnFinality and create an API key.

Getting tBNB from the Faucet

You need tBNB to pay gas fees on testnet. Use one of these faucets:

BNB Chain Faucet – Official faucet, requires a Twitter account.
Thirdweb Faucet – Provides 0.01 tBNB per day.
Chainstack Faucet – Alternative option.

Tip: If a faucet is dry, try another or wait for the cooldown period.

Adding BSC Testnet to MetaMask

Open MetaMask and click the network dropdown.
Click Add Network.
Enter the following details:
- Network Name: BNB Smart Chain Testnet
- RPC URL: https://data-seed-prebsc-1-s1.bnbchain.org:8545 (or your preferred endpoint)
- Chain ID: 97
- Currency Symbol: tBNB
- Block Explorer URL: https://testnet.bscscan.com
Click Save.

Alternatively, use Chainlist to add the network with one click.

Testing with curl

Verify your RPC endpoint is working:

curl -X POST https://bnb-testnet.api.onfinality.io/public \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

Expected response:

{"jsonrpc":"2.0","id":1,"result":"0x733a3b"}

Common Pitfalls and Debugging

1. Wrong Chain ID

If transactions fail with "chainId mismatch," ensure your wallet or dApp uses chain ID 97 (0x61).

2. Insufficient tBNB

Check your balance using:

curl -X POST <rpc-url> \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["<your-address>","latest"],"id":1}'

If balance is 0, use a faucet.

3. Rate Limiting

If you get HTTP 429 errors, reduce request frequency or switch to a private endpoint.

4. eth_getLogs Disabled

Some public endpoints disable eth_getLogs. Use a provider that supports it or switch to WebSocket for real-time logs.

5. WebSocket Connection Drops

Ensure your client handles reconnection. Example with WebSocket:

const WebSocket = require('ws');
const ws = new WebSocket('wss://bnb-testnet.api.onfinality.io/public');
ws.on('open', () => {
  ws.send(JSON.stringify({jsonrpc:"2.0", method:"eth_subscribe", params:["newHeads"], id:1}));
});
ws.on('message', (data) => console.log(data));

When to Use a Managed RPC Provider

While public endpoints are fine for quick tests, production-grade development often requires:

Higher rate limits – Avoid throttling during automated testing.
Archive data – Query historical state for debugging.
WebSocket reliability – Stable connections for event subscriptions.
Dedicated nodes – Isolated resources for consistent performance.

OnFinality provides all these options for BNB Smart Chain Testnet. You can start with a free shared endpoint and upgrade as needed. Check RPC pricing and supported networks for details.

Key Takeaways

BNB Smart Chain Testnet (chain ID 97) is an EVM-compatible test network using tBNB.
Use public endpoints for light testing; consider managed providers for heavier workloads.
Always verify chain ID and faucet availability before deploying.
WebSocket support is essential for real-time dApps.
Debugging common issues like rate limits and disabled methods saves time.

Frequently Asked Questions

Q: What is the BNB Smart Chain Testnet RPC URL?
A: Public URLs include https://data-seed-prebsc-1-s1.bnbchain.org:8545 and https://bnb-testnet.api.onfinality.io/public. For a private endpoint, sign up at OnFinality.

Q: How do I get tBNB?
A: Use the official BNB Chain faucet or third-party faucets like Thirdweb. Most require a social login.

Q: Can I use the same contract on testnet and mainnet?
A: Yes, because both networks are EVM-compatible. Just ensure you use the correct chain ID and redeploy.

Q: Why are my transactions pending forever?
A: Check your tBNB balance and gas price. Also ensure you are connected to the correct RPC endpoint.

Q: Does OnFinality support BSC Testnet?
A: Yes, OnFinality offers both shared and dedicated endpoints for BNB Smart Chain Testnet. Visit BNB Testnet network page for details.

Related resources

Originally published at OnFinality.

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