Intermittent vs Fasting Center

The intermittent fasting tracker that shows the biology happening inside you in real time: Fed, Lipolysis, Ketosis, Autophagy. Ad free fasting app. No account required. Most fasting apps give you a countdown clock and a streak to protect. Intermittent does something different. It shows you exactly which biological phase your body is in right now, and explains the science behind it with cited primary sources, not marketing copy. If you have ever wondered how to track fasting properly, or what is actually happening during a fast, this is the fasting tracker built for that question. WHY FASTING WORKS Intermittent fasting works because of what happens between meals, not just the absence of food. As your fast progresses, your body moves through distinct phases: burning through glucose reserves, shifting into fat burning lipolysis, entering ketosis, and eventually triggering autophagy, the cellular repair process linked to longevity and metabolic health. Understanding these transitions is what separates intentional fasting from guesswork. Intermittent maps every stage so your goals are grounded in biology, not motivation. KEY FEATURES PHASE AWARE FASTING TIMER A real time timer that tracks six biological phases: Fed, Early Fasting, Lipolysis, Ketosis, Autophagy, and Deep Fast. Each phase links to a free science article with primary sources cited. EVERY FASTING PROTOCOL, ONE APP Supports 12:12, 14:10, 16:8, 18:6, 20:4, OMAD (One Meal A Day), 36 hour, 48 hour, and 72 hour fasts. FREE FASTING SCIENCE LIBRARY A full library of fasting articles covering intermittent fasting, ketosis, autophagy, insulin response, and more. No subscription. No account. No paywall. SMART HYDRATION TARGET A science backed hydration goal that adapts to your weight, sex, age, and fasting duration. WEIGHT AND PROGRESS TRACKING Log your weight after each fast and track trends over time. Includes streak heatmap, phase reach history, and estimated fat vs glucose energy usage. PRIVATE CIRCLE AND END OF FAST REFLECTION Share your fast with a small private group. Applause only responses. No comparison. No gamification. HOME SCREEN WIDGET AND CROSS DEVICE SYNC Keep your fasting timer visible with a home screen widget. Your data syncs across devices privately without third party trackers. WHO IT IS FOR Intermittent is built for adults who want to understand fasting, not be coached through it. If you follow research on metabolic health, read about longevity, or want a fasting routine grounded in biology rather than points or streaks, this app is for you. Suitable for both beginners and experienced fasters. HOW IT WORKS Choose your fasting protocol, from 12:12 to extended fasts Start your timer and track your biological phase in real time Tap any phase to read the science and log your reflection at the end No account required to start. No subscription required to access the library.

Free fasting tracker and timer for intermittent fasting, OMAD, and extended water fasts. No ads, no account needed. Fasting Center is built around your numbers, not generic guesses. Start a fast, follow 17 fasting stages on a live ring, and see weight, fat loss, and energy use projected from your own body stats, then measured against what actually happened. TRACK YOUR FAST - Timer with stage markers: fat burning, ketosis, autophagy, and more - Any schedule: 16:8, 18:6, 20:4, OMAD, multi-day extended, or open-ended - Live Activity and Dynamic Island on iPhone, home screen widgets - Edit start and end times when life happens - Projected vs measured weight loss, side by side ASK YOUR FASTING ASSISTANT - Ask about your fasts, your weight, or how you feel during a fast - Answers based on your own log and the fasting.center knowledge base - Runs the calculators for you - how long to a goal weight or a body fat target - Free, with a daily limit of questions TWO CALCULATORS - Extended fast: total weight change, fat, water, glycogen, and protein loss day by day - Intermittent fasting: daily calorie deficit and expected weight change for your window - Personalized from your sex, age, height, weight, body fat, and activity MEASURE YOUR PROGRESS - Log weight, body fat, waist, ketones, glucose, and blood pressure - Rate energy, hunger, motivation, and stress during a fast - Apple Health sync: weight and body fat flow in automatically - Charts over 24h, 7 days, 30 days, 90 days, and a year - Import your history from Zero and Easy Fast YOUR DATA, YOURS - Free, no ads, no subscription - Works fully as a guest; optional sign-in with Apple or Google for cloud backup and sync - Delete your data and account anytime, completely Whether you are planning your first extended fast or fine-tuning a routine you have run for years, Fasting Center shows you what to expect and what actually happened. Fasting Center is a planning and estimation tool and does not provide medical advice. Consult a healthcare provider before starting an extended fast, especially if you have any underlying health conditions.