Hi, I'm Ohm. ISSA & PESA certified,
coaching online from Bangkok.

Training and nutrition calculators, built by a certified coach.

Five tools that answer the questions that come up most in coaching — and give you a plan, not just a number. Free, no sign-up, and everything runs in your browser.

The tools

The guides

Fifteen guides covering how to use these numbers — what they mean, where they break down, and what to do when the plan stops working. See all guides.

Why another calculator site

Most fitness calculators give you one number and no context. Worse, a lot of them borrow authority they do not have — invented reviewing doctors, statistics attributed to research that is never named, "data from our users" on sites that collect no data.

These tools are built by someone who uses them with actual clients, every number comes from a published equation or an accepted range, and where an estimate is shaky the page says so. That is the whole difference. More about who writes this.