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 Training Calculator

Plan your marathon buildup by calculating a weekly mileage target and ideal training paces from your goal finish time. Use it when structuring a training block weeks before race day.

Goal Marathon Time (minutes)

Current Weekly Mileage (miles)

Weeks Until Race (weeks)

Experience Level

Fill in the required fields to see your result.

Key differences

	Marathon Fueling Calculator	Marathon Training Calculator
Category	Running	Running
Inputs required	4	4
Result	Total Carbs Needed (grams)	Easy Run Pace (min/mile)
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.	Plan your marathon buildup by calculating a weekly mileage target and ideal training paces from your goal finish time. Use it when structuring a training block weeks before race day.