Free Running Tool

Marathon Fueling Calculator

Calculate your marathon nutrition plan with exact gel timing, carb targets & sodium needs. Get a personalized race fueling strategy in minutes.

Features

  • Personalized carb targets based on your goal time
  • Gel timing schedule with exact mile markers
  • Sodium and electrolyte requirements
  • Choose your preferred gel brand
  • Printable race day fueling card

How It Works

Enter your marathon goal time, body weight, and preferred gel brand. We calculate your hourly carbohydrate needs (30-90g/hour depending on intensity), then create a precise fueling schedule with gel intake at optimal intervals to prevent bonking.

Benefits

  • Avoid the dreaded 'wall' with proper fueling
  • Practice race-day nutrition in training
  • Know exactly when and what to consume
  • Prevent GI distress with gradual intake

Frequently Asked Questions

How many gels do I need?

Typically 4-7 gels for a marathon, depending on your pace and carb tolerance. Faster runners need more carbs per hour.

When should I start taking gels?

We recommend starting at 30-45 minutes into the race, before you feel fatigued, to stay ahead of your energy needs.

Try Marathon Fueling Calculator Free

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