Carb & Fueling Calculator
Tell us how long and how hard you're training. We'll give you a carbs-per-hour target, and how many gels and bottles that means.
Your fueling targets
Practical example
Fueling plan sorted. Now the workout.
Type the ride or run you’re fueling for — “3 hr endurance with 3 x 20 min tempo” — and TextFit builds the structured session and sends it to your Garmin, Wahoo, or Apple Watch.
Free to start. No account, no sign-up. Works in any language.
How the targets work
The recommendations follow the standard endurance fueling framework: for sessions under an hour your glycogen stores are enough (around 30 g/hr only if you're going hard), efforts of 1–2.5 hours call for about 60 g/hr, and anything longer needs 90 g/hr or more. Under-fueling long sessions is the most common self-inflicted bonk in endurance sport: your body only stores roughly 90 minutes of hard-effort glycogen.
Above ~60 g/hr a single sugar can't be absorbed fast enough, so higher intakes rely on mixed carb sources (glucose plus fructose — most modern gels and drink mixes are blended this way). The gut is trainable like any muscle: practice your race-day fueling plan in training first, and build up toward the higher rates gradually.