I built 125+ free calculators (no signup, 100% client-side) — would love feedback
Hey IH! Over the past few months I've been building FreeFixo (https://freefixo.com) — a collection of 125+ free calculators and tools for finance, tax, real estate, health, legal, and business.
Why I built it: almost every calculator site out there hides behind a signup, buries you in popups, or quietly ships your inputs to a server. I wanted the opposite — everything runs 100% client-side in your browser, no account, no paywall, no tracking of what you type.
Stack: React + TanStack Router, Vite, deployed on Cloudflare Pages. Fully static and prerendered for SEO (the whole thing is a client-side SPA but every route ships real HTML for crawlers).
What I've learned so far building in public:
- SEO for a JS SPA is brutal until you prerender — Bing literally flagged "insufficient content" on pages where the tool grid was client-rendered. Had to inject static tool lists + content into the HTML.
- Programmatic SEO scales fast (I have 425+ long-tail calculator pages) but you have to watch canonical/duplicate-content traps carefully.
- Distribution is 10x harder than building. The tools were the easy part.
Would genuinely love feedback on:
- Which tools feel most useful vs. filler?
- The privacy-first angle — does "no signup, runs in your browser" actually matter to you, or is it table stakes?
- Monetization: currently planning ads (AdSense). Is there a cleaner way to monetize a free-tool site without nuking the privacy positioning?
Happy to answer anything about the build. Thanks for reading!
425+ programmatic long-tail pages with intent-clean traffic is a rare asset. adsense on tools sites is like $2-8 rpm territory, so meaningful only above 100k monthly, thin below.
the higher-leverage lever is hooking a related saas or lead-gen product to the calculators. mortgage calc points to refi comparison, invoicing calc to a freelancer tool, tax calc to prep affiliates. if intent matches, per-session revenue lifts 10-100x vs adsense.
which 5 of your 125 tools have the highest search volume so far, and are any of them adjacent to a paid product you'd naturally build next?
I'm curious when you realized you were building an SEO business rather than a collection of calculators.
Was there a point where your decisions started being driven more by search behavior than by adding new tools?