Websums is a suite of 18 free personal-finance and small-business calculators that run entirely in your browser — no sign-up, no paywall. Mortgage (with UK stamp duty + US state property tax), salary, compound interest, FIRE, ROAS, burn rate, unit economics and more. Just clear answers, fast.

Hey Product Hunt 👋 I'm Jeremy, founder of EllaByte. I built Websums out of a small, recurring frustration: every time I needed a quick financial sum, I'd land on a calculator that was slow, buried under ads, or demanded a sign-up first. So Websums is the opposite of that — 18 free calculators for personal finance and small business: mortgage, stamp duty, salary, compound interest, FIRE, ROAS, burn rate, unit economics and more. Everything runs client-side in your browser, there's no sign-up, and there's a built-in £/$/€ currency switch plus US state property-tax presets, so it works on both sides of the Atlantic. It's completely free, and I'm actively adding to it. I'd genuinely love your feedback — and especially: which calculator should I build next? Thanks for taking a look 🙏