About Atrical

Hi, I'm Kristjan

I got into triathlon to get my health back on track, and it stuck. Along the way I wanted pacing tools that understood real courses, so I started building them.

Why Atrical exists

Most pacing calculators give you one flat number per kilometre, as if every course were a running track. Real courses have hills, and real race plans need to know where they are. Atrical reads your course file and tells you where to hold back, where to push, and what your splits should look like.

It's free and there's no sign-up.

How it's built

Honestly: most of Atrical's code was written with AI assistance. Call it vibe-coded. What isn't left to chance is the maths. Every calculation is based on published research or standard physics, the sources are linked, and the places where we made our own choices are spelled out on the methodology page. The core calculations are also covered by automated tests.

Atrical gives estimates, not guarantees, and it isn't coaching or medical advice. If something looks off, I'd like to hear about it. You can reach me through hiis.eu.