How many carbs do I need per hour of cycling?

It depends on intensity and how long you are out. A single carbohydrate source (glucose or maltodextrin) oxidises at no more than ~60g/hr, so that is the ceiling for shorter rides. For easy endurance rides 30-40g/hr is plenty, and for tempo and threshold efforts aim for 60g/hr. On rides over about 2.5 hours, dual-source mixes (glucose:fructose roughly 2:1) let well-trained riders push to 90g/hr. Train your gut to tolerate higher carb rates gradually — going straight to 90g/hr untrained usually causes GI distress.

How much should I drink per hour?

Aim for 500-1000ml per hour depending on intensity, temperature and sweat rate. A practical approach is to weigh yourself before and after a ride to estimate your sweat rate. Each kilogram of weight lost equates to roughly 1 litre of fluid deficit.

When should I start eating on a ride?

Begin fuelling 30 minutes into the ride. Do not wait until you feel hungry or depleted — by then it is too late. Set a timer on your bike computer to remind you every 20 minutes. Early and consistent fuelling prevents bonking.

Should I use gels or bars?

Both work well. Bars are better at lower intensities when you can chew easily. Gels are more practical at higher intensities. A mix of both prevents flavour fatigue on long rides. Always take gels with water unless they are isotonic.

How many electrolyte tablets do I need?

One tablet per 500ml bottle is standard. For hot conditions or heavy sweaters, you may need two per bottle. Sodium is the key electrolyte lost in sweat — aim for 500-1000mg sodium per hour in warm weather.

BikeCalcs

Ride Nutrition Calculator

Plan your fuelling strategy for any ride with carbs, fluid and feeding schedule.

Ride Distance

Planned ride distance — duration drives the fuel totals, so set both

Estimated Duration

Total expected ride time — carbs and fluid are totalled over this window

IntensityHarder efforts raise carb burn and sweat rate (≈20 g/h easy up to ≈90 g/h flat-out)

Body Weight

Scales the fluid estimate — heavier riders sweat more (75 kg = baseline)

How We Calculate This

Nutrition Calculation

Carbs needed = Carb rate (g/hr) × Fuelling hours

Fluid needed = Sweat rate (ml/hr) × Duration

Fuelling begins ~30 minutes into the ride, once stored glycogen starts to run down — so the carb total covers the duration minus that first half hour. The sweat baseline for each intensity is scaled by your body weight against a 75 kg reference rider, because heavier riders lose more fluid. The solid-carb need is then split into ~40g bars and ~25g gels alongside electrolyte drink for variety and gut tolerance.

Frequently Asked Questions

Related Calculators

Ride Calorie Calculator

Estimate total calories needed for a ride based on duration and intensity.

Hydration Calculator

Calculate fluid intake requirements based on duration and temperature.

Carb Loading Calculator

Plan carbohydrate loading for race preparation.

Electrolyte Calculator

Calculate sodium and electrolyte needs for long rides.

Bonk Calculator

Estimate when glycogen stores will deplete without fuelling.

Last updated: March 2026

All calculations are estimates. Always verify results and consult a professional bike fitter where appropriate.