Triathlon Bike Size Calculator

Triathlon bike sizing is fundamentally different from road bike sizing. While both use centimeter frame measurements, triathlon and TT bikes feature steeper seat tube angles (76-80° vs 72-74° on road bikes), shorter top tubes, and aerobar extensions that create a completely different riding position. Most riders need a frame 1-2cm smaller than their road bike size.

The aero position on a tri bike prioritizes reducing frontal area while preserving hip angle for efficient pedaling and a strong run off the bike. Stack and reach measurements are more important than traditional frame size, as the aerobar pad position is built around these reference points. Our calculator accounts for your full body measurements to recommend optimal frame geometry.