Bitquery
Onchain GraphQL APIs & DEX APIs
Blockchain
Blockscout
Multichain block explorer REST API (with Etherscan-compatible JSON-RPC)
Chainlink
Build hybrid smart contracts with Chainlink
Covalent
Multi-blockchain data aggregator platform
Etherscan
Ethereum explorer API
Helium
Helium is a global, distributed network of Hotspots that create public, long-range wireless coverage
Nownodes
Blockchain-as-a-service solution that provides high-quality connection via API
Steem
Blockchain-based blogging and social media website
The Graph
Indexing protocol for querying networks like Ethereum with GraphQL
TWZRD Agent Intel
Solana on-chain agent trust scoring via MCP; 4 free tools to score, resolve and verify AI agent wallets
Watchdata
Provide simple and reliable API access to Ethereum blockchain