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.
Exact caffeine timing and mg/kg targets for marathons, 70.3s, and ultras, plus how to use coffee, gels, and gum without wrecking your gut or sleep on race day.
Read: Caffeine Timing for Endurance Races →Stomach issues during races usually come from pacing, heat, drink concentration, or poor gut training. Here's how to spot the cause and fix it properly.
Read: Why You Keep Getting Stomach Problems During Races (And How to Fix It) →Most endurance athletes don't need random salt tabs. Here's how to estimate sodium per hour from sweat rate, weather, and race duration without overdoing it.
Read: How Much Sodium Do You Need Per Hour During an Endurance Race? →Your liver glycogen drops 40% overnight. Here's exactly what to eat before a race, when to eat it, and what to skip so you don't blow up before mile 10.
Read: What to Eat the Morning Before a Race →Heat changes your sweat rate, gut function, and sodium needs. Here's exactly how to adjust your carbs, fluids, and sodium when race day turns hot and humid.
Read: How to Adjust Your Race Nutrition Plan for Hot Weather →Your gut adapts to processing fuel at effort, but only if you practice. Here's the science behind gut training and an 8-week protocol to get race-ready.
Read: Gut Training for Endurance Athletes →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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