Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Marathon Fueling Calculator

Calculates how many grams of carbohydrates you need during a marathon or long race based on body weight, expected finish time, intensity, and weather. Use it during race planning to build your on-course nutrition strategy.

Body Weight (lbs)

Expected Race Time (minutes)

Race Intensity

Weather Conditions

Fill in the required fields to see your result.

Running

Marathon Taper Calculator

Calculates the recommended weekly training volume for each week of your pre-race taper, scaling down from peak mileage based on your recovery rate, taper length, and race distance. Ideal for marathon and ultramarathon preparation.

Peak Weekly Mileage (miles)

Taper Duration

Race Distance

Recovery Rate

Fill in the required fields to see your result.

Key differences

	Marathon Fueling Calculator	Marathon Taper Calculator
Category	Running	Running
Inputs required	4	4
Result	Total Carbs Needed (grams)	Final Week Mileage (miles)
What it does	Calculates how many grams of carbohydrates you need during a marathon or long race based on body weight, expected finish time, intensity, and weather. Use it during race planning to build your on-course nutrition strategy.	Calculates the recommended weekly training volume for each week of your pre-race taper, scaling down from peak mileage based on your recovery rate, taper length, and race distance. Ideal for marathon and ultramarathon preparation.