Personalized, hour-by-hour fueling plans built from sports science — not guesswork. Adjusted for your body, your race, and your weather.
Every distance has different fueling demands. We account for that.
Racing a specific event? Browse 400+ races with historical weather data and race-specific fueling strategies.
Race type, target time, body weight, experience level. Takes about 60 seconds.
Hour-by-hour carb, fluid, and sodium targets — adjusted for race-day weather at your location.
Save your plan, export to PDF. Tape it to your bike, screenshot it for your watch. Go race.
Each plan is tailored to your body weight, race distance, target time, experience level, and predicted weather conditions.
Not just totals — exact targets for every hour of your race, with ramp-up pacing built in.
40–120 g/hr based on your experience level and gut tolerance, using glucose + fructose science.
Sweat rate estimation tuned by temperature, humidity, and intensity. Sodium dosing to match.
Auto-fetches forecast data for your race location. Plans adapt to heat, humidity, and rain risk.
Specific recommendations — gels, chews, drink mix, or real food — mapped to each hour.
Warnings for high heat, gut fatigue in long races, and hyponatremia risk — before race day.
Current sports science consensus for events over 2.5 hours, using dual-transport glucose + fructose pathways.
We estimate your losses and recommend 70–80% replacement — full replacement can cause more problems than it solves.
Remarkably consistent across paces. We use this to estimate your burn, then target 30–50% caloric replacement.
Sweat rate scales with temperature above 60°F. We model this alongside humidity to estimate your fluid needs.
Formulas based on Jeukendrup (2014), Sawka et al. (ACSM Position Stand), Gagge & Stolwijk sweat models, and current ISSN guidelines. All calculation logic is open and testable — no black boxes.
Build a 100-mile ultramarathon nutrition plan with hourly carbs, real food, hydration, caffeine, crew timing, drop bags, and overnight fueling by hour.
Read: 100-Mile Ultramarathon Nutrition Plan →Build an Ironman hydration plan with fluid and sodium targets, bike bottle math, aid-station timing, run-course cups, and practical hot-race backup plans.
Read: Ironman Hydration Plan →Build a 50-mile ultra nutrition plan with carb, fluid, sodium, real-food, caffeine, drop-bag, and aid-station targets for your first long ultramarathon.
Read: 50-Mile Ultra Nutrition Plan →Learn how to fuel long runs during marathon training: when to start, carbs per hour, what to practice, and how to avoid race-day gut issues on race day.
Read: How to Fuel Long Runs During Marathon Training →Hyponatremia in endurance athletes usually starts with overdrinking. Learn the warning signs, risk factors, and safer race-day hydration rules for long races.
Read: Hyponatremia in Endurance Athletes →Use the carb loading calculator to find your daily grams-per-kg target, when to start, and how to spread 600-800 grams across familiar race-week foods.
Read: The Complete Guide to Carb Loading →Every formula traces back to Jeukendrup, Sawka et al., and ACSM position stands — not blog posts.
All calculation logic is transparent and unit-tested. You can see exactly how your plan is built.
No paywall, no account required, no “premium tier.” Build unlimited plans and export PDFs for free.
Your race nutrition plan takes 60 seconds to build. It's free, no account needed, and you'll walk away with an hour-by-hour blueprint you can actually use.
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