The Scaling Test Network (STN) is a Bitcoin SV test network specifically intended for testing large blocks. It is the fourth permanent network defined in Bitcoin SV, complementing mainnet (the main network), testnet (the public test network), and regtest (local test network). The STN is included as a standard network in the latest builds of Bitcoin SV. It can be selected by using stn=1 in bitcoin.conf instead of testnet=1 or regtest=1. The Scaling Test Network has been implemented to reduce the impact of scalability testing on testnet and to preserve testnet as a network for testing of applications build on top of Bitcoin SV without requiring testnet users to make significant hardware available. The Scaling Test Network has been designed to be compatible with the majority of software implementations while maintaining separation from the testnet.