Multi-chain RPC API
One JSON-RPC endpoint, 40+ chains, no API key.
Traditional RPC providers (Alchemy, Infura, QuickNode) make you sign up, manage an API key, and pick a monthly plan with rate-limit tiers — per chain. BlockRun gives your AI agent a single endpoint for 40+ chains and charges $0.002 per call in USDC via x402. No accounts, no keys, no tiers.
BlockRun RPC vs traditional providers
| Feature | BlockRun RPC | Alchemy / Infura / QuickNode |
|---|---|---|
| Signup | None — wallet signature per call | Account + email required |
| API key | None | Required |
| Pricing | $0.002/call in USDC, pay-per-use | Monthly plans + compute-unit tiers |
| Rate limits | None (pay-per-call) | Tiered by plan |
| Chains | 40+ via one endpoint | Per-chain projects/keys |
| Built for | Autonomous AI agents | Human developers + dashboards |
| Settlement | On-chain USDC, tx hash returned | Off-chain billing |
How it works
Send a standard JSON-RPC request and choose the chain in the path — POST /v1/rpc/{network}. With no payment header you get an HTTP 402 quoting the exact price ($0.002); add an x402 payment header (a wallet signature) and you get the result, settled on-chain.
curl -X POST https://blockrun.ai/v1/rpc/ethereum \
-H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"eth_blockNumber","id":1}'
# → 402 with price $0.0020 + Base USDC payment instructionsFAQ
What is a multi-chain RPC API?
A multi-chain RPC API is a single endpoint that speaks JSON-RPC 2.0 to many blockchains. Instead of integrating a separate provider and key for Ethereum, Solana, Base, Polygon and so on, you send your request to one URL and choose the chain in the path. BlockRun fronts 40+ chains this way.
How is BlockRun's RPC different from Alchemy, Infura or QuickNode?
Those providers require an account, an API key, and a monthly plan with rate-limit tiers. BlockRun's RPC needs none of that — you pay $0.002 per call in USDC via the x402 protocol, with no signup and no key. It's designed for autonomous AI agents that pay per call from a wallet.
Which chains are supported?
40+ verified chains including Ethereum, Base, Solana, Polygon, BNB Smart Chain, Arbitrum, Optimism, Avalanche, zkSync, Bitcoin, Litecoin, Dogecoin, Near, Sui, XRP Ledger, Polkadot and more. EVM eth_* methods and non-EVM JSON-RPC both work.
How much does it cost?
A flat $0.002 per JSON-RPC call, settled in USDC on Base. A JSON-RPC batch is priced per element. There are no subscriptions, monthly minimums, or rate-limit tiers.
Do I need an API key?
No. Send a request with no payment header and you get an HTTP 402 quoting the exact price; add an x402 payment header (a wallet signature) and you get the result. No accounts, no keys, no dashboards.
Start querying any chain
Fund a wallet with USDC on Base and hit /v1/rpc/{network} — no registration, no API keys.