Stacks (STX) API Documentation

Stacks

Stacks (STX) is a Bitcoin layer for smart contracts using Proof of Transfer and signer-based block validation, with the Nakamoto release activated in 2024 to strengthen its Bitcoin-based settlement model. Smart contracts are written in Clarity, while nodes process Stacks transactions and maintain principal balances, contract code and data, block state, and Bitcoin-linked consensus information. Because Stacks anchors its operation to Bitcoin while exposing its own programmable state, applications combine Bitcoin settlement references with Stacks-specific accounts, contracts, transactions, and PoX data.

Stacks API Methods and Endpoints

NOWNodes exposes Stacks's interface, plus a few others, depending on what your integration needs: its native Stacks RPC for reading chain state and broadcasting transactions. Archive mode extends this interface to historical states and data beyond standard retention.

Browse the interfaces below for endpoint details, request parameters, response formats, and integration examples. Create an API key, select Mainnet or Testnet, choose the required interface, and start sending requests from your application.

Weighing Stacks RPC providers against each other? Read the comparison guide on our blog — this page stays focused on integration reference.