This ultra-simple app makes $8,500 per month | Starter Story

The first sentence of the Starter Story case study says it plainly: "This website right here that converts HTML to PDF makes $8,500 a month." The host walks through PDFShift.io, a tool that does exactly one thing—you send it HTML code via API, and it returns a PDF file—and shows how a single, boring, technical utility can generate serious recurring revenue without venture capital, without a team, and without building anything flashy.

The business model: usage-based pricing on a single function

PDFShift.io's pricing page reveals the strategy. There is a small free tier to let people try the service, but after that, customers pay per PDF converted. The pricing is "usage-based," meaning the more you use it, the more you pay, and the host notes that some customers end up on plans costing $500 per month. The key insight is that this is not a product people buy once—it is a recurring need. Developers and businesses that rely on generating PDFs from web pages do it constantly, and they will pay monthly to keep the pipeline running.