stack127 is a toolbox and reference hub for indie hackers, solo developers, and digital creators who build and run projects online. Use its free tools to calculate SaaS metrics such as MRR and churn, estimate Amazon KDP royalties, check domains and DNS, and plan hosting and storage. Its directories help you compare platform fees, discover CLI apps and self-hosted software, and find places to launch a product. Reference pages explain facts such as domain status codes and software licenses. Built by Ravi Teja KNTS, stack127 turns repeated questions and practical project work into tools and resources other builders can use. Most of its tools are open source through stack127labs on GitHub.