SuperCalc - Free Financial Calculators

I got frustrated with existing financial calculators that were either:

- Buried in ads and pop-ups

- Required signup to see results

- Had confusing interfaces

- Missing key features I needed

As someone who frequently helps friends with financial planning, I realized there's

a gap: people need professional-grade calculators that are actually free and easy to

use.

SuperCalc exists because financial literacy tools shouldn't be paywalled. Whether

you're calculating retirement savings, comparing mortgages, or planning taxes, these

tools should be accessible to everyone.

Started with 15 calculators, now at 273+ and growing based on user requests. Every

calculator is built to be genuinely helpful, not to capture emails or upsell premium

plans.

Hey IH! 👋

I just launched SuperCalc—a collection of 273+ financial calculators that are

actually free to use.

The Problem:

Every time I needed a calculator (retirement planning, mortgage comparison, tax

estimation), I'd hit the same wall:

- Sites drowning in ads

- "Sign up to see results"

- Broken on mobile

- Missing the exact calculator I needed

What I Built:

Started with 15 calculators I personally needed. Now at 273+ covering:

• Finance (compound interest, retirement, net worth)

• Tax (income tax, capital gains, sales tax)

• Real Estate (mortgage, rent vs buy, cap rate)

• Business (valuation, break-even, cash flow)

• Health (BMI, TDEE, pregnancy)

Tech stack: Next.js, TypeScript, static export (blazing fast)

What Makes It Different:

- Zero ads, zero tracking, zero signup

- Mobile-first design

- Each calculator has formulas + explanations

- 100% free forever (not freemium)

My Question for IH:

How do you monetize genuinely helpful tools without ruining the UX? I'm

bootstrapping this and want to keep it free, but also exploring:

- Affiliate links (tasteful)

- Optional "buy me a coffee"

- Premium API for developers

What's worked for you?

👉 https://supercalc.dev/

Would love your feedback! Which calculators would you add?