ATNAX - Online Calculators

What Is ATNAX?

ATNAX is a collection of carefully built online calculators for finance, health, and more. Every tool here was created because the founder needed it and couldn't find a version that was accurate, fast, and free of clutter. The site exists to solve that problem — not to chase traffic, not to sell anything, just to give you a reliable answer quickly.

The calculators span a growing range of practical topics. On the finance side: compound interest, mortgages, salary conversion. On the health side: BMI, body fat percentage, body frame size. More categories are in development. Whatever the calculation, the goal is the same: give you the exact result, explain what it means, and get out of the way.

Why You Can Trust the Results

Every formula on ATNAX is sourced from a primary reference — an academic paper, WHO or CDC guidelines, or an official government methodology. We implement the math exactly as published and test every calculator against known values before it goes live. There are no approximations and no creative rounding.

All calculations run entirely in your browser. Nothing you enter is ever sent to a server. There are no cookies, no sign-ups, no tracking of any kind. The whole site is static HTML and JavaScript delivered over HTTPS — your data never leaves your device.

How to Use These Tools

Every calculator updates results instantly as you type — no submit button, no waiting. Results are broken down so you can see not just the final number but the reasoning behind it. Where the math is non-trivial, there is an explanation of the formula and what each input affects.

If you spot an error, or if you need a calculator that isn't here yet, get in touch. The wishlist is real and drives what gets built next.