Race Fueling Calculator
Calculate total carbohydrate grams for a triathlon or a single sport and organise your fuelling strategy.
2:20:00
- Pre-start
- 30 g
- Bike
- 70 g · 60 g/h
- Run
- 45 g · 60 g/h
The pre-start amount is consumed before the start, not during the swim.
Total planned carbs 145 g
How to use it
Choose Triathlon or Single sport. For triathlon, enter pre-start carbohydrates, expected swim duration and, for cycling and running, duration and your g/h target. Swim duration counts only towards total time; pre-start carbohydrates remain a fixed amount. For running or cycling alone, the calculation uses duration and g/h. For swimming alone, only the fixed pre-start amount is shown.
What you need to know
This calculator is a planning tool, not personalised guidance. Carbohydrate tolerance requires testing and gut training. Higher intake targets require an appropriate combination of carbohydrate sources and systematic testing in training. The tool does not calculate water, sodium or caffeine needs, or your pre-race meal.
Read the related article
Your fuelling plan is just the beginning.
Building carbohydrate tolerance and distributing intake across the different sports depends on intensity, conditions and your gut tolerance. Together, we can design and test your fuelling strategy before each race.
Methodology & Sources
Total triathlon plan = fixed pre-start carbs + Bike g/h × cycling hours + Run g/h × running hours. Swim duration is not multiplied by a carbohydrate intake rate. For running or cycling alone, grams = g/h × duration in hours. For swimming alone, only the selected pre-start intake is shown. General guidelines include approximately 30–60 g/h for longer efforts and up to around 90 g/h for prolonged exercise with multiple transportable carbohydrates, usually glucose or maltodextrin sources combined with fructose. These values are indicative and require individualisation and testing in training.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4008807/
Last updated: 23 June 2026