What this result means
Endurance racing carbohydrate intake is often expressed as grams per hour, with higher bands for longer efforts. This page maps finish duration to those hourly targets.
Use it when you know how long you expect to be racing — from a goal time or recent result — and want a hourly carb number before building a gel schedule.
A 3:30 marathon (~210 minutes) typically falls in the 60–90 g/hour band used for long events. A 45-minute 10K sits in a lower band where hourly carbs matter less.
Pair the hourly number with the race fuel timeline to spread gels across the clock.
Calculation method
Duration buckets follow ISSN/ACSM-style sports nutrition guidance documented on /methodology. Output is grams carbohydrate per hour, not total race grams.
Gut tolerance and training the gut are not modeled. Start lower in practice if you are new to in-race fueling.
Not medical advice.
Frequently asked questions
How many carbs per hour should I take in a marathon?
Long races often target 60–90 g/hour for trained runners, depending on duration and tolerance. Enter your expected marathon time to see the band this tool uses.
Do shorter races need carbs?
Events under about an hour rarely need in-race carbs for performance. The calculator reflects lower hourly guidance for short durations.
How do I turn g/hour into gels?
Multiply hourly grams by hours racing for a total, then divide by carbs per gel — or open the energy board or fuel timeline for an integrated view.
Do I need an account?
No.