Start a real fasting countdown right in your browser. Track your metabolic phases, see when you enter fat burning and ketosis, and get notified at every milestone. No app needed.
Intermittent fasting is one of the simplest and most evidence-backed approaches to improving metabolic health, but knowing where you are in your fast makes a real difference. This free browser-based fasting timer shows your elapsed time, remaining time, and current metabolic phase so you can fast with confidence.
Your body transitions through five distinct phases during a fast: Fed State, Catabolic, Fat Burning, Ketosis, and Deep Ketosis. Each phase comes with different metabolic benefits. By seeing exactly when you cross each threshold, you can make informed decisions about when to break your fast and maximize the benefits you are after.
This timer runs entirely in your browser. Your data is saved in localStorage so it persists across page reloads. No account, no download, no tracking. For the full experience with streaks, history, and push notifications, try the Fasted app.
Answer 8 questions about your lifestyle and goals to find the perfect intermittent fasting protocol. Personalised recommendation.
Calculate your ideal fasting and eating windows based on your schedule, sleep time, and lifestyle. Get a personalised daily timeline.
Estimate your body fat percentage using the US Navy method or BMI method. Free calculator with fitness category and ideal range.
The Fasted app saves every fast automatically, builds your streak calendar, and shows detailed stats so you can see your consistency improve over time.
Free to use — No account required
