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
