Nutrition Calculator
Calculate your carb, hydration, and electrolyte needs for your next session.
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Duration
Intensity
Total Carbs
0
g
0g / hour
Total Hydration
0
ml
0ml / hour
Total Electrolytes
0
mg
0mg / hour
How this is calculated
Carbohydrate targets scale with intensity: roughly 40–90g per hour from easy aerobic work up to race effort.
Hydration assumes a standard ~625ml per hour under moderate conditions (~15°C). Adjust up in heat or if you sweat heavily.
Sodium recommendations start for sessions of 90 minutes or longer, and increase slightly for efforts over 2–4 hours. These are starting points — use your own sweat rate and gut tolerance as the final guide.
FAQ
- How many carbs per hour by intensity?
- Carbohydrate targets scale with intensity: about 40g/hour for easy (Z1–Z2), 60g for moderate (Z3), 75g for hard (Z4), and 90g for race (Z5) effort.
- How is hydration estimated?
- Hydration assumes a standard about 625ml per hour under moderate conditions (~15°C). Increase intake in heat or if you sweat heavily.
- When do electrolyte recommendations apply?
- Sodium recommendations start for sessions of 90 minutes or longer and increase slightly for efforts over 2–4 hours. Treat them as starting points and adjust for your sweat rate and gut tolerance.
- Is this calculator a substitute for a personalized fueling plan?
- No. It provides evidence-based starting ranges for carbs, fluid, and sodium. Race-day fueling should still be practiced in training and adjusted for heat, altitude, and individual tolerance.
Updated July 2026
