Built in Rajasthan. For the World.

My name is Harsh. I grew up in Rajasthan, India, and like a lot of people here, I didn't have easy access to the kind of financial and health tools that professionals in bigger cities take for granted. When I needed to figure out how much home loan I could actually afford, or understand whether my BMI was healthy, I found most tools online were either locked behind paywalls, plastered with intrusive ads, or just plain inaccurate.

That frustration sat with me. I kept thinking: the math isn't secret. The formulas for mortgage amortization, compound interest, calorie calculations, BMI — these are all public knowledge, well-established, and freely available in any textbook. So why were people paying for them? Why were they being tracked, emailed, or upsold just to run a simple calculation?

Cloud Calculators App started as a personal project. I wanted one place where I could run any calculation I needed — accurately, quickly, on my phone — without giving up my email address or wading through three pop-ups first. I built the first few calculators for myself, then kept going because the need clearly existed for anyone dealing with financial planning, health goals, or everyday math problems.

Today, Cloud Calculators App offers 100+ calculators across finance, health, math, and everyday utilities — all completely free, no account required, and all running locally in your browser so your data stays yours. I build and maintain this under PapaSiddhi, my personal projects platform. The mission hasn't changed: professional tools should be available to everyone, everywhere, regardless of where they live or how much money they have.

Accuracy isn't a marketing claim — it's a design requirement. Every formula we use is sourced from authoritative references: IRS publications for tax calculators, WHO standards for health tools, peer-reviewed clinical research for nutrition formulas, and established financial mathematics for mortgage and investment tools.

For health calculators, we use the Mifflin-St Jeor equation for calorie and BMR calculations — validated in a major study in the Journal of the American Dietetic Associationas more accurate than the older Harris-Benedict formula for most adults. Our BMI tool uses the standard WHO formula and includes context about the limitations of BMI as a standalone metric, because accurate tools require honest explanations.

For financial calculators, our mortgage and loan tools use the standard amortization formula identical to what banks use. Our income tax calculator is updated with each year's official IRS bracket tables and standard deduction amounts. Our compound interest calculator uses the mathematically precise future value of an annuity formula — not approximations.

When formulas are updated (new tax year brackets, revised clinical guidelines), we update the calculators. We also clearly mark what each calculator covers and what it doesn't — because the most accurate calculator is one that knows its own scope. Our income tax tool clearly states it covers federal tax only; our calorie tool notes that TDEE estimates vary ±10% due to individual factors. We won't overstate what a tool can tell you.