Intermittent Fasting Calculator

Calculate your intermittent fasting schedule, eating windows, and fasting periods. Free online IF calculator for weight loss and health.

Calculator

Intermittent Fasting Calculator

Calculate your personalized intermittent fasting schedule, optimal eating windows, and fasting periods. Plan your IF routine for weight loss, health benefits, or lifestyle optimization.

Intermittent Fasting Calculator

Fasting Method

Schedule Preferences

Custom Fasting Schedule

Experience Level

Fasting Goals

Results

Enter your preferences above to see your personalized intermittent fasting schedule.

Understanding Intermittent Fasting

What is IF?

Intermittent fasting is an eating pattern that cycles between periods of fasting and eating, focusing on when you eat rather than what you eat.

Fasting vs Starving

Fasting is voluntary and controlled, while starvation is involuntary. Fasting can be stopped at any time.

Metabolic Switch

During fasting, your body switches from using glucose to using stored fat for energy, producing ketones.

Autophagy

Extended fasting periods may trigger autophagy, a cellular cleanup process that removes damaged cells.

Popular Fasting Methods

Time-Restricted Feeding

16:8 Method: 16 hours fasting, 8 hours eating
18:6 Method: 18 hours fasting, 6 hours eating
20:4 Method: 20 hours fasting, 4 hours eating
14:10 Method: 14 hours fasting, 10 hours eating

Other Methods

5:2 Method: 5 days normal eating, 2 days 500-600 calories
Eat-Stop-Eat: 24-hour fasts 1-2 times per week
Alternate Day: Fasting every other day
Warrior Diet: 20 hours fasting, 4 hours eating

Benefits and Tips

Potential Benefits

  • Weight loss and fat burning
  • Improved insulin sensitivity
  • Enhanced mental clarity
  • Increased energy levels
  • Cellular repair (autophagy)
  • Simplified meal planning

Fasting Tips

  • Start gradually (12-14 hours)
  • Stay hydrated during fasting
  • Listen to your body
  • Break fast with nutritious foods
  • Don't overeat during eating windows
  • Be consistent with your schedule

Features

  • • Multiple fasting methods
  • • Customizable schedules
  • • Experience level guidance
  • • Goal-specific recommendations
  • • Flexible timing options
  • • Free to use

Perfect For

  • • Weight loss goals
  • • Health optimization
  • • Lifestyle improvement
  • • Metabolic health
  • • Simplified eating
  • • Wellness routines

Important Disclaimer

This calculator provides general recommendations for educational purposes only and should not replace professional medical advice. Intermittent fasting may not be suitable for everyone, including pregnant women, people with eating disorders, those with certain medical conditions, or individuals taking specific medications. Always consult with a healthcare provider before starting any fasting regimen, especially if you have diabetes, low blood pressure, or other health concerns.

Frequently Asked Questions

What is intermittent fasting?

Intermittent fasting is an eating pattern that cycles between periods of fasting and eating. It doesn't specify which foods to eat but rather when you should eat them. Common methods include 16:8, 18:6, and 5:2 fasting.

How long should I fast?

The duration depends on your goals and experience. Beginners often start with 12-14 hours, while more experienced fasters may do 16-20 hours. The 16:8 method (16 hours fasting, 8 hours eating) is popular for weight loss.

Can I drink water during fasting?

Yes, you should drink plenty of water during fasting periods. You can also have black coffee, tea, and other non-caloric beverages. Avoid drinks with calories, sugar, or artificial sweeteners.