Intermittent Fasting Scheduler
Pick a scheme and your first meal - see your exact eating and fasting windows and meal times.
What intermittent fasting is and the main schemes
Intermittent fasting is an eating pattern that splits the day into an eating window and a fasting window. The numbers name the hours: 16/8 means 16 hours fasting and an 8-hour eating window, the most popular scheme for beginners. The planner above builds the exact schedule for your chosen scheme and first meal.
- 14/10 - the gentlest start, a 10-hour eating window;
- 16/8 - the balanced default: eat from roughly midday to 8pm;
- 18/6 - a tighter window for the experienced;
- 20/4 - one main meal and a small one, advanced.
How to pick a scheme for beginners
Start with 14/10 or 16/8 and tighten the window only once fasting feels easy. Jumping to 20/4 in the first week usually ends in a breakdown. Follow how you feel - if you get dizzy or overeat in the window, widen it again.
What you can eat and drink
During the fast you can have water, black coffee and unsweetened tea - they do not break the fast. In the eating window eat normally, with a focus on protein and vegetables. Fasting sets the timing, not the quality of the diet, and it works by creating a calorie deficit rather than by magic.
Benefits: what the research shows
Intermittent fasting has been studied for years, and reviews describe its effects on body weight and metabolism [1]. A large 2025 network meta-analysis compared fasting schemes with ordinary calorie restriction on cardiometabolic outcomes [2]. Time-restricted eating is linked with a range of health effects [3], and reviews unpack the metabolic mechanisms [4]. The takeaway: fasting works about as well as a plain deficit, so pick the pattern you can keep to.
Intermittent fasting for women
Women are often more comfortable starting with gentler schemes (14/10, 16/8), since tight windows affect appetite and wellbeing more. With cycle irregularities, when planning a pregnancy or with hormonal issues, discuss the scheme with a clinician.
Who it is not for
Intermittent fasting is not suitable during pregnancy or breastfeeding, with an eating disorder, with diabetes on medication or with several chronic conditions. Weakness, dizziness or breakdowns are a signal to soften the scheme, not to push through.
Frequently asked questions
What is intermittent fasting in simple terms?
An eating pattern that splits the day into an eating window and a fasting window. 16/8 means 16 hours fasting and an 8-hour eating window.
Which intermittent fasting scheme is best for beginners?
14/10 or 16/8. Start gentle and tighten the window only once fasting feels easy.
What can I drink during the fast?
Water, black coffee and unsweetened tea. They do not break the fast.
Does intermittent fasting help you lose weight?
Yes, by creating a calorie deficit. Trials find it works about as well as ordinary calorie restriction.
Who should not do intermittent fasting?
Not during pregnancy or breastfeeding, with an eating disorder, or with diabetes on medication without a doctor.
Sources
- Metabolic Effects of Intermittent Fasting. Annu Rev Nutr, 2017. PubMed
- Intermittent fasting strategies and their effects on body weight and cardiometabolic outcomes. BMJ, 2025. PubMed
- Health Benefits of Intermittent Fasting. Microb Physiol, 2024. PubMed
- Intermittent fasting and human metabolic health. Rev Med Chil, 2023. PubMed
This planner is informational and does not replace medical advice. Intermittent fasting is not suitable during pregnancy or breastfeeding, with an eating disorder, or with diabetes on medication - decide with a clinician.