⏳Fasting Timer

About this tool

Pick a schedule, press Start after your last meal and the progress ring fills towards your goal, with time elapsed, time to go and the clock time it ends. Forgot to start? Edit the start time. Ending a fast logs it; the history shows the last fortnight, your streak, how often you met the goal and your average fast. It keeps running if you close the tab.

What intermittent fasting does — and doesn't

Time-restricted eating confines meals to a daily window: 16:8 means sixteen hours without food and eight hours to eat, often by skipping breakfast or a late snack. Its appeal is simplicity, and for many people it is an easy way to eat less. Controlled trials have found weight loss similar to ordinary calorie reduction — helpful, not magical — and claims about specific hours switching on fat burning or ‘autophagy’ come mostly from animal studies, which is why this timer shows time rather than invented stages. Black coffee, tea and water are generally fine during a fast. It is not suitable for everyone: talk to a doctor first if you are pregnant or breastfeeding, have diabetes or take medication affected by meals, are under 18, or have a history of eating disorders. Not medical advice. The fast is saved in this browser only and nothing is sent. The calorie calculator sets intake for the eating window (How daily calorie needs are calculated — BMR, activity multipliers and what a deficit means), the water intake calculator covers hydration (How much water you should drink a day — what the evidence says, and where 8 glasses came from), and the habit tracker records other daily goals.

Frequently asked questions