Blockchain.com vs Solana JSON RPC

Blockchain.com's free Explorer API returns JSON data for Bitcoin blocks, transactions, and addresses with no signup or key, alongside a Statistics/Charts API, an Exchange Rates API, and a WebSocket feed for real-time block and mempool notifications. Browser callers can opt individual GET requests into CORS by appending a cors=true parameter; this read-only data API is a separate product from Blockchain.com's API-key-gated Exchange trading API.

Solana's public JSON-RPC clusters expose the full read/write RPC surface — accounts, transactions, blocks, and WebSocket subscriptions — with no signup or API key required. They're free to call, but Solana's own docs are explicit that the shared public endpoints are rate-limited to roughly 100 requests per 10 seconds per IP and are not intended for production traffic, pointing serious usage toward a dedicated third-party RPC provider instead.