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    Carb Mix Calculator

    Hitting 90g of carbs per hour takes the right glucose-to-fructose blend. Set your hourly target and this calculator works out the glucose and fructose split plus exactly how many gels and drink-mix scoops to carry.

    Your fuel target

    Set an hourly carb goal and your products.

    30g60g90g120g

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    Last updated: June 2026Reviewed by: Bryan Collins, founder

    How this calculator works

    Carb totals are split between gels and drink mix by your chosen ratio, then converted to items using the carbs-per-gel and per-scoop you enter. Above 60 g/hour the target is split into glucose and fructose at a 1:0.8 ratio to reflect multiple-transportable-carbohydrate absorption.

    Assumptions

    • • Even fuelling across the race
    • • Glucose:fructose 1:0.8 above 60 g/hour
    • • Gut tolerance built up in training for high intakes

    Limitations

    • • Individual GI tolerance varies widely
    • • Does not account for solid food or on-course nutrition brands

    Who this is for

    • • Triathletes and cyclists fuelling long races
    • • Athletes targeting 80-120 g/hour for 70.3 and Ironman
    • • Anyone planning how many gels and scoops to carry

    Who this is not for

    • • Athletes with diagnosed carbohydrate-malabsorption conditions (seek medical advice)
    • • Very short races under ~75 minutes (carbs matter less)

    References

    Carb Mix Calculator FAQ

    Scientific References

    Jeukendrup AE. Carbohydrate intake during exercise and performance. Nutrition. 2010.

    Foundational review of multiple transportable carbohydrates and oxidation rates