Summary
Choosing the right RPC endpoint is critical for dApp performance and reliability. This guide walks through key evaluation criteria—rate limits, chain IDs, testnet reliability, and when to upgrade to managed or dedicated infrastructure—across five popular networks: Ethereum Sepolia, Polygon, Solana Devnet, Base Sepolia, and peaq. Whether you're prototyping on a testnet or scaling on mainnet, understanding these factors helps you avoid bottlenecks and ensure smooth development.
In practice, the useful question is not just whether an endpoint exists. Teams should check Solana methods, devnet support, request patterns, and whether shared or dedicated access fits the workload. That turns the page from a definition into a decision tool: it helps you decide what to test first, what belongs in staging, and when a production workload may need stronger isolation or clearer request visibility. If you already know the network you need, open /networks/ethereum-sepolia after using this checklist so you can test the endpoint against your real methods.
Key Takeaways
- Public RPC endpoints are free but come with rate limits and no support terms; they are suitable for development and light testing.
- Always verify the correct chain ID for each network to avoid transaction failures or wallet misconfigurations.
- Testnet endpoints (Sepolia, Solana Devnet, Base Sepolia) are essential for safe prototyping but may have lower reliability than mainnet.
- Managed RPC services offer higher rate limits, dedicated throughput, and better availability for production workloads.
- Dedicated nodes provide full control, archive data access, and consistent performance for high-traffic dApps.
- peaq is a Polkadot parachain with EVM compatibility; its RPC endpoints support both JSON-RPC and Substrate APIs.
- Evaluate latency, geographic distribution, and support for WebSocket connections when choosing an RPC provider.
Key Criteria for Evaluating RPC Endpoints
When selecting an RPC endpoint, developers should consider several factors that directly impact application performance and reliability. The table below outlines the most important criteria, what to check, and why each matters.
| Criterion | What to check | Why it matters |
|---|---|---|
| Rate Limits | Maximum requests per second (RPS) and daily/monthly caps | Exceeding limits causes throttling or dropped requests, breaking your dApp under load. |
| Chain ID | Correct chain ID for the network (e.g., 11155111 for Sepolia) | Wrong chain ID leads to transaction failures or sending funds to the wrong network. |
| availability & Reliability | Historical availability percentage and support terms documents | Downtime directly affects user experience; testnets may have lower availability than mainnet. |
| Latency | Response times from different geographic regions | High latency slows down dApp interactions; choose endpoints close to your user base. |
| WebSocket Support | Availability of WSS endpoints for real-time updates | Essential for applications requiring live data streams (e.g., order books, notifications). |
| Archive Data | Support for historical state queries (archive nodes) | Needed for analytics, explorers, and applications that query past block data. |
| Privacy | Whether the provider logs or shares request data | Public endpoints may log IPs; private endpoints offer better privacy for sensitive operations. |
Solana RPC decision checklist
Use this checklist to turn the Solana RPC question into a practical infrastructure decision instead of a generic provider comparison.
Start with the workflow you need to support, then verify the endpoint, method coverage, test environment, and next step before relying on it in production.
- List the exact RPC methods, chains, and environments your app will call.
- Test with the same request pattern your frontend, backend, bot, dashboard, or indexer will use.
- Check whether archive, trace, WebSocket, testnet, analytics, or dedicated-node access is actually required.
- Review pricing, usage visibility, and upgrade paths before moving sustained traffic.
| Criterion | What to check | Why it matters |
|---|---|---|
| Workload fit | Does the provider support the Solana RPC methods and environments your product depends on? | A provider that works for a quick read may still be a poor fit for wallets, trading systems, indexers, or release pipelines. |
| Operational visibility | Can the team see request volume, errors, limits, and usage patterns? | Visibility makes it easier to debug failed requests and plan capacity before users feel the problem. |
| Scaling path | Is there a clear path from shared RPC to higher-capacity plans or dedicated nodes? | The right starting point should not force a rebuild when traffic or reliability requirements increase. |
Ethereum Sepolia RPC
Sepolia is Ethereum's primary testnet for smart contract development. Its chain ID is 11155111 (0xaa36a7) and uses test ETH as gas. Public endpoints like https://eth-sepolia.api.onfinality.io/public are free but rate-limited (typically 100-1000 RPS). For heavier testing or continuous integration, a managed endpoint with higher limits is recommended. Sepolia replicates mainnet behavior closely, making it ideal for pre-launch validation.
- Chain ID: 11155111
- Currency: Sepolia ETH (testnet)
- Public endpoint: https://eth-sepolia.api.onfinality.io/public
- Rate limits: ~100 RPS on public, higher on managed plans
- Use case: Smart contract testing, dApp prototyping, CI/CD pipelines
Polygon RPC
Polygon (formerly Matic) is a popular Ethereum sidechain with chain ID 137 and native token POL. Its mainnet RPC endpoints are widely available, including https://polygon.api.onfinality.io/public. Public endpoints support basic dApp interactions but may throttle under high load. For production dApps with significant traffic, consider a dedicated node to ensure consistent performance and access to archive data.
- Chain ID: 137
- Currency: POL
- Public endpoint: https://polygon.api.onfinality.io/public
- Rate limits: ~100 RPS on public, higher on managed plans
- Use case: DeFi, gaming, NFT marketplaces, high-throughput dApps
Solana Devnet RPC
Solana Devnet is the testing environment for Solana programs. Unlike EVM chains, Solana uses a different RPC specification and has a chain ID of 901 (often referred to as 2305 in some tools). The public endpoint https://api.devnet.solana.com is free but rate-limited (typically 100 RPS). For more reliable testing, especially when deploying programs or simulating high throughput, a managed Solana RPC endpoint is advisable.
- Chain ID: 901 (sometimes 2305)
- Currency: SOL (testnet)
- Public endpoint: https://api.devnet.solana.com
- Rate limits: ~100 RPS on public, higher on managed plans
- Use case: Solana program development, testing, and integration
Base Sepolia RPC
Base Sepolia is the testnet for Base, an OP Stack L2 built by Coinbase. Its chain ID is 84532 and uses Sepolia ETH as gas. Public endpoints like https://base-sepolia.api.onfinality.io/public are available for testing. Since Base Sepolia mirrors mainnet behavior, it's perfect for testing L2-specific features like bridging and gas optimization before mainnet deployment.
- Chain ID: 84532
- Currency: Sepolia ETH (testnet)
- Public endpoint: https://base-sepolia.api.onfinality.io/public
- Rate limits: ~100 RPS on public, higher on managed plans
- Use case: L2 dApp testing, bridging, gas optimization
peaq RPC
peaq is a Polkadot parachain focused on DePIN (Decentralized Physical Infrastructure Networks). It is EVM-compatible with chain ID 3338 and native token PEAQ. Public endpoints like https://peaq-rpc.publicnode.com are available, but for production DePIN applications, a dedicated node provides the reliability and performance needed for machine-to-machine transactions. peaq also supports Substrate-native APIs via Polkadot JSON-RPC.
- Chain ID: 3338
- Currency: PEAQ
- Public endpoint: https://peaq-rpc.publicnode.com
- Rate limits: ~100 RPS on public, higher on managed plans
- Use case: DePIN, machine economy, IoT dApps
When to Move from Public to Managed or Dedicated Infrastructure
Public RPC endpoints are great for development, testing, and low-traffic applications. However, as your dApp grows, you'll likely encounter rate limits, inconsistent performance, or privacy concerns. Here's a quick guide on when to upgrade:
- Managed RPC: When your dApp exceeds 100 RPS consistently, or you need an support terms for availability.
- Dedicated Node: When you require archive data, custom configuration, or documents throughput for high-traffic production.
- OnFinality offers both managed RPC plans and dedicated node deployments across all five networks, with global coverage and 24/7 support.
Frequently Asked Questions
What is the chain ID for Sepolia?
Sepolia's chain ID is 11155111 (0xaa36a7 in hex).
What is the chain ID for Polygon?
Polygon mainnet chain ID is 137. The testnet (Amoy) uses 80002.
What is the chain ID for Solana Devnet?
Solana Devnet uses chain ID 901 (sometimes displayed as 2305 in EVM-compatible tools).
What is the chain ID for Base Sepolia?
Base Sepolia chain ID is 84532.
What is the chain ID for peaq?
peaq mainnet chain ID is 3338.
Are public RPC endpoints safe for production?
Public endpoints are generally safe for development and testing, but they have rate limits and no support terms. For production, use a managed or dedicated RPC service to ensure reliability and performance.
How do I get testnet tokens for Sepolia, Solana Devnet, or Base Sepolia?
Testnet tokens are available from official faucets. For Sepolia and Base Sepolia, use a Sepolia ETH faucet. For Solana Devnet, use the Solana faucet to get devnet SOL.
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