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 $0.003 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 | $0.003/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 ($0.003); 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 $0.0030 + 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 $0.003 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 $0.003 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.