Open DIY endurance-fueling tools
Mix your own carbs, and train your gut to use more.
Two free, evidence-based tools for endurance athletes who'd rather understand their fueling than buy it. The math is shown; the papers are cited. No accounts.
Mixing calculator
Make your own fuel
Turn a target and the bottles you ride with into a per-carrier recipe: grams, concentration, sodium placement, drinking schedule.
- table sugar183 g
- maltodextrin92 g
Open the calculator
Gut-training planner
Train your gut
A week-by-week plan to raise the carbs per hour your gut absorbs, with an honest feasibility check that refuses unrealistic timelines.
Build a plan
Built on the research
Glucose:fructose ratios (Hearris 2022), gut adaptation (Costa 2023) and transporter limits (Jeukendrup 2017). Every recommendation is sourced, not asserted. See the methodology →
Learn the ingredients
Ingredient reference → Eight DIY staples: composition, osmolarity, sourcing, sources cited.
Glossary → Plain-English on g/h, osmolality, % w/v and the rest.
Brand specs → Carbs, glucose:fructose ratio and sodium for popular gels and mixes, from the labels.
Mixed from pantry staples, a DIY drink costs a fraction of branded gels, a side-benefit of doing it yourself, not the point. Educational tool, not medical advice.