NOWNodes API: How to Connect to Blockchain RPC Endpoints

What the NOWNodes API Is

The NOWNodes API is a hosted blockchain node service that exposes JSON-RPC endpoints for many networks behind a unified access model. Instead of running and syncing your own node, you send standard RPC requests to a NOWNodes endpoint and receive responses from infrastructure the provider operates.

Because the interface is standard JSON-RPC for most chains, existing libraries such as web3.js, ethers.js, web3.py, and similar clients can often be pointed at a NOWNodes URL with minimal code changes. The main differences from a self-hosted node are authentication, endpoint naming, and any provider-specific rate or plan limits.

NOWNodes supports a broad set of networks, and the exact list can change over time. Always confirm current chain support and endpoint formats in the official NOWNodes documentation before building around a specific network.

• Hosted access to many blockchain nodes via HTTP and WebSocket
• Standard JSON-RPC methods for EVM and many non-EVM chains
• Single API key model across supported networks
• No node syncing or server maintenance required

How NOWNodes Endpoints and API Keys Work

NOWNodes access is typically tied to an API key that you include in the request URL or in a header, depending on the endpoint style. The most common pattern is a base URL per network with your key appended as a path segment or query parameter.

The exact URL format varies by chain and by the endpoint type (HTTP versus WebSocket). For example, an Ethereum-style HTTP endpoint often looks like a host plus a network path plus your key. WebSocket endpoints use the ws:// or wss:// scheme with a similar structure.

Treat your API key like a password. Anyone who has it can consume your quota, so avoid committing it to public repositories or exposing it in client-side code where it can be scraped.

• API key is usually passed in the URL path or a request header
• Each supported network has its own endpoint path
• HTTP endpoints are used for request/response JSON-RPC calls
• WebSocket endpoints are used for subscriptions and push updates
• Keep keys server-side or in environment variables

https://<host>/<network>/<api-key>
wss://<host>/<network>/<api-key>

Making a First Request with the NOWNodes API

Once you have an endpoint and key, you can test connectivity with a simple JSON-RPC call. For EVM chains, eth_blockNumber is a lightweight method that returns the latest block height and confirms the endpoint is responding.

Send a POST request with a JSON body containing jsonrpc, method, params, and id. The response should include a result field with the block number in hexadecimal for EVM chains.

If you receive an authentication error, check that the key is correct and placed in the expected position for that network's endpoint. If you receive a method-not-found error, confirm the method is supported on that chain.

• Use POST with Content-Type: application/json
• Start with a cheap method like eth_blockNumber
• Check the result field and the id match your request
• Verify the endpoint path matches the network you intend to query

curl -X POST https://<host>/<network>/<api-key> \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

Supported Networks and Common Use Cases

NOWNodes covers a wide range of networks, including major EVM chains and several non-EVM ecosystems. The exact catalog evolves, so treat any list as a snapshot rather than a permanent guarantee.

Typical use cases include wallet balance lookups, transaction broadcasting, smart contract reads, block and event queries, and indexer or analytics backends. For high-volume or latency-sensitive workloads, evaluate whether the provider's throughput and reliability fit your needs.

If you need a specific chain, verify support before designing your architecture. Some networks may be available only on certain endpoint types or plan tiers.

• EVM chains for wallets, dApps, and contract interactions
• Non-EVM chains for chain-specific RPC methods
• Transaction broadcast and receipt polling
• Block, log, and event queries for indexing
• WebSocket subscriptions for real-time updates

NOWNodes API Documentation and Free Access

The official NOWNodes documentation is the authoritative source for endpoint formats, supported chains, authentication details, and any plan or rate information. Because these details can change, always check the docs before relying on a specific URL pattern or limit.

NOWNodes has historically offered a free tier or trial access for testing, but the exact terms, request limits, and available chains can change. Do not assume a free tier will cover production traffic; verify current terms directly.

When evaluating any RPC provider, including NOWNodes, test with realistic request patterns and confirm error handling, rate-limit behavior, and failover options.

• Use official docs for current endpoint and chain lists
• Confirm free-tier limits before production use
• Test rate-limit and error responses under load
• Plan for failover if uptime matters to your application

Practical Considerations Before You Commit

RPC providers differ in latency, throughput, chain coverage, and support responsiveness. NOWNodes is one option among several, and the right choice depends on your specific chains, traffic profile, and reliability requirements.

If your workload requires guaranteed performance or dedicated infrastructure, compare providers on measurable criteria rather than marketing claims. Run your own benchmarks against the endpoints you plan to use.

For teams already using a multi-provider strategy, NOWNodes can serve as one endpoint alongside others. Keep your integration abstracted so you can switch or add providers without rewriting application logic.

• Benchmark latency and success rates for your key methods
• Check chain coverage against your roadmap
• Review rate limits and overage behavior
• Abstract provider URLs so you can swap or add endpoints
• Confirm support channels and response times