I built a free, no-login, unlimited AI invoice tool. Here are the 4 features and the 5 5 3 dunning matrix behind it.

Cross-post notice: this is the canonical version. Reposts on Medium, Hashnode, and Indie Hackers will link back here. A few months ago I shipped a free invoice generator. The kind of tool freelancers find at 11pm when a client wants an invoice and they don't want to register on a CRM just to send a PDF. The whole product runs under four hard constraints I refused to break: 100% online — open the URL, use it. No install, no desktop app, no browser extension. Works on any laptop, tablet, or...