What it can do
48h, 60h, 72h — or any length 24–168h
Presets for the common durations, a slider for everything else up to seven days.
Backdate if you're already fasting
Start in Past lets you log the real start time, not when you happened to open the app.
Stage content through 72 hours
Stage descriptions and educational callouts for common fasting milestones from the fasting library, through the first 72 hours of a session.
History, not resume
Completed fasts are saved. There is no mid-fast resume, so plan the length before you start.
How the Extended Fasting Tracker works
What the tracker actually does
The Extended Fasting Tracker runs sessions from 24 up to 168 hours (one to seven days). Quick-select presets are 48h, 60h, and 72h; the slider covers everything in between and beyond in hour increments. If you're already fasting when you open the app, Start in Past lets you backdate the start by up to the fast length minus one hour, so the timer matches real elapsed time.
You can only run one fast at a time — the Extended Fasting Tracker and the Intermittent Fasting Tracker are mutually exclusive. Starting an extended fast takes over the timer until you end or cancel it.
What you see during a session
A large count-up timer and your target duration. Through the first 72 hours, the screen also surfaces content from our fasting library: a short stage description, body-state notes, and educational milestone callouts for common fasting phases such as ketosis and autophagy. These are orientation markers, not live biomarker readings. Beyond 72 hours, the timer and milestone state keep running; the hour-by-hour detail stops.
History, not resume
Completed, cancelled, and ended-early extended fasts are all saved to your history with duration and date range. There is no mid-fast resume — if a session ends, you start a new one. There is also no automatic daily restart: Extended is for deliberate one-off sessions, not a repeating loop.
How to use it
Decide the length before you start and stick to it, so you are not negotiating with yourself at hour 30. Treat milestone content as orientation, not prescription. Break the fast with a controlled first meal rather than a reward meal, and return to normal tracking the next day.
App Features

Intermittent Fasting Tracker
Free intermittent fasting tracker — pick a window, run it with a live timer, and keep a rolling record of what you actually did.

Weight Tracking
Free weight tracker — log daily, edit any entry inline, and watch the trend over time.

Walking Tracker
Free walking tracker — start a timer, pick your pace, and let pause/resume handle real-life interruptions.

Calorie Tracker
Free manual calorie tracker — log meals once, save them to My Foods, and watch your daily remaining calories update live.


90-Day Challenge
The sponsored structure layer — set a goal weight, pick 30 to 180 days, and the app aggregates every food, walking, and weight entry into one timeline.
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Frequently asked questions
What durations does the Extended Fasting Tracker support?
Sessions can run from 24 to 168 hours, which covers one to seven days. Quick-select presets are available for 48h, 60h, and 72h, and the slider handles the rest in hour increments. It is built for deliberate one-off sessions, not a daily repeating fasting loop.
Can I log a fast that already started?
Yes. Start in Past lets you backdate the beginning of the session by up to the fast length minus one hour. That keeps the timer aligned with real elapsed time when you started fasting before opening the app. You still choose the target duration before the session runs.
What is shown during a long fast?
A running timer against your target duration, so you can see how far into the fast you are. As the hours add up, the screen also pulls in stage content from the fasting library — short notes on what is typically happening in the body at common milestones such as ketosis and autophagy. Treat these as general orientation, not live readings from your own body.
Can I run extended fasting and intermittent fasting at the same time?
No. The two trackers are mutually exclusive. Starting an extended fast takes over the timer until you end or cancel that session. That separation matters because extended fasting is a deliberate one-off event, while the Intermittent Fasting Tracker is the daily schedule loop.
Can I resume an extended fast after ending it?
No. Once an extended fast ends, it is saved as completed or cancelled in your history and cannot be resumed mid-session. If you want to keep going, you start a new fast. That keeps the record honest: one session means one continuous fasting block.
Use this feature now
Extended Fasting Tracker
The web app works on every device, including iPhone. Android users can also install the native app from the Play Store.