Eliminate a tiny daily friction with a single-purpose, no-login web tool

Many people bump into the same tiny daily friction: a 30‑second formatting task, a quick unit conversion, or stripping metadata from a file that interrupts flow dozens of times a week. Knowledge workers, students, developers and creators—roughly the 500 million users implied by the addressable market estimate—are willing to trade a few cents a month or a one‑time payment for a tool that saves repeated small interruptions. Build a single‑purpose, no‑login web utility that does one thing extremely well (for example, instant text cleaning, URL shortener with copy, or one‑click CSV to JSON conversion), hosted on the edge as a tiny static/Serverless app with zero tracking and a clear privacy guarantee. Offer a fully functional free tier, a simple subscription or tip jar (targeting $1–$4/month or $12–$40/year), and a lightweight pro feature set that justifies paying without account friction. This market is attractive now because micro‑SaaS and indie hacking have matured (market score 92/100) and infrastructure like serverless/edge hosting materially lowers engineering and hosting costs, while privacy‑first preferences increase adoption for no‑login tools. With an estimated $20B market assuming 500M users willing to pay $40/year and a revenue potential score of 80/100, a well‑positioned single‑purpose app can be economically viable even at modest conversion and low CAC. To stand out, focus on frictionless UX, extreme performance, transparent privacy, and distribution through niche blogs, search, and developer communities rather than broad paid acquisition; consider open‑source or audited privacy claims to build trust. Honest challenges are discoverability, scaling conversions beyond niche audiences, and maintaining repeat value for a tool that solves a very small problem, but the low build and hosting cost profile makes experimentation low risk.