Nutrition Tool

Intermittent Fasting Calculator

Plan a fasting and eating window that works around your real routine. Useful for structure, not for pretending you are a monk because you skipped breakfast.

Intermittent fasting is not suitable for everyone. Do not use this tool without professional advice if you are under 18, pregnant or breastfeeding, have diabetes medication, a history of eating disorders, unexplained weight loss or another medical condition affected by food timing.

Your Schedule

16:8 Fasting Window

Daily Timing Plan
— Fasting Window
— Eating Window
— First Meal
— Last Meal Ends
Ready when you are Choose your schedule and generate your plan.
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Add your preferred fasting schedule to create a practical daily window.

Common Fasting Windows

12:12 A simple overnight break from food. Often easier for people who want routine without forcing a major change to meals.
14:10 A middle-ground option that can still allow breakfast or an earlier dinner, depending on how you set the window.
16:8 A popular structure with an eight-hour eating window. It can be convenient, but it is not automatically better than other ways of eating.
18:6 and beyond More restrictive windows can make it harder to get enough food, protein and energy around training. Bigger is not always better.

How To Make It Work

Use fasting as a structure, not punishment.
The eating window should help make meals simpler. It should not become a reason to ignore hunger, recovery or proper nutrition.
Protein and total calories still matter.
Fasting does not replace the basics. You still need enough food, protein, fruit, vegetables and recovery for your goal.
Train around the window where practical.
Some people prefer to eat before training, others after. Choose the routine that lets you train properly and recover well.
Keep hydration sensible.
Water, tea, coffee and electrolytes can matter more than people expect, especially during hot weather or hard training days.

Related Nutrition Tools

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