SaaS

Use a free page to sell developers a one-job tool

Build a tool other apps pay to use that does one boring developer job, charge by how much it's used, and use a free single-use tool page to bring in developers.

The hard part: ranking a free tool page high enough to feed steady paid API usage.

Setup 1 weekRuns $30/moYour time A weekly check-inNeeds ClaudeSupabaseVercelStripe

Who pays

Developers and apps that need the job done at volume pay a monthly usage plan for the API. Casual users of the free tool page bring in ad revenue.

How to build it

  1. Build an API for one job

    Choose one narrow, repetitive job developers need, such as HTML to PDF or video to transcript, and build the API for it with Claude Code or Cursor.

  2. Host it to handle traffic spikes

    Deploy the API on Vercel or Cloudflare Workers so it can handle traffic that comes in bursts.

  3. Issue keys and track requests

    Set up Supabase to issue API keys and record each request, so you know how much each customer uses.

  4. Bill monthly based on usage

    Connect Stripe metered billing to the usage records in Supabase and charge customers a monthly bill based on what they used.

  5. Attract developers with a free tool

    Publish a free single-purpose tool page that does the job once per visit. Run AdSense on it and put a clear link to the API docs for developers who need volume.

Sources on X

  • danielkbuilds · Sep 22, 2026

    Secondhand account from danielkbuilds about Cyril Nicodème. Nicodème launched an HTML-to-PDF API in May 2018 after shipping about 70 side projects, of which only 4 made money. According to the post, monthly recurring revenue went from $3.5K in 2020 to $6.5K in 2021 to about $7.5K. At that point a company offered $500K to buy it, but the deal fell through when the terms were renegotiated. The post, dated 2026-09-22, says it was making about $9K a month.

  • scheemunai · Aug 17, 2026

    The operator gives their own numbers for a YouTube transcript tool site: about 2.5K from AdSense and about the same from subscriptions. They call it a simple pass-through tool with low retention. They say its bigger value is as a large lead generator for their paid TranscriptAPI.

Ideas are curated from public posts and untested by us. Read the full note.