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Tool

Hyrox hydration & electrolyte calculator

Estimate how much to drink and how much sodium to take before and during a Hyrox race - based on your size, your expected finish time, and the conditions on the day.

165 lb

Not sure? Most first-timers finish 90-120.

Conditions
Your typical sweat level

Before (last 2-3 hrs)

-

water

During the race

-

sipped at transitions

Electrolytes

-

packets (~1000mg Na each)

Your timeline

    Full race-day nutrition guide →
    Not medical advice. These are general estimates for a healthy adult. Real sweat and sodium losses vary a lot between people. Never try a new hydration plan for the first time on race day, do not over-drink plain water (it can dangerously dilute your sodium), and check with a professional if you have any medical conditions.

    How this hydration calculator works

    The tool estimates your sweat loss from your bodyweight, your expected race duration, the conditions, and how heavily you usually sweat. It then suggests water to drink before and during the race and how much sodium to replace - because in a Hyrox, cramping and the late-race fade are far more often a sodium and pacing problem than a calorie problem.

    Why sodium matters more than you think

    Sweat carries roughly 800-1000mg of sodium per litre. Across a 90-minute race in a hot hall you can lose well over a litre, which is why a single electrolyte serving (such as an LMNT packet) about 30-60 minutes before your wave makes such a difference. Read the full timing breakdown, including exactly when to take it, in the Hyrox race day nutrition guide, and adjust for your event using the city guides - a humid race like Miami or Singapore needs far more than a cool indoor one.

    Then dial in the rest of your race

    Pair your hydration plan with target splits from the pacing calculator, predict your finish with the finish-time predictor, and log what actually worked in the Hyrox Training Logbook so your next race plan is built on your own data.