Sweat rate — personal hydration calculator

Weigh yourself before and after a session (same conditions, minimal clothing). Add the fluid you drank during. Get your sweat rate in L/h and how much to drink during future races.

Peso ANTES (kg) Peso DESPUÉS (kg)

Líquido tomado durante (ml) Duración (min)

Calculate

Repeat in different conditions (cool day vs hot day, easy vs hard) to map your real sweat rate. The number changes with heat, humidity, intensity and altitude.