Intermittent Fasting Timer

Start a fast, track your fasting window in real time, get reminders, and keep your fasting history in one simple tool.

Ready to start

Choose a protocol to begin

Goal --

Start --

End --

Choose your fasting plan

Custom fasting hours

Body status

Select a fasting plan to see stage guidance.

Your body guidance will update automatically as your fasting session progresses.

Fasting history

Click or tap a day to inspect your sessions.

For educational purposes only. Not medical advice.

What Is an Intermittent Fasting Timer?

An intermittent fasting timer or intermittent fasting tracker is a simple tool that tracks how long you have been fasting and when your target fasting window ends. Instead of calculating start and end times manually, you can choose a fasting plan, start the timer, and see your progress update in real time.

This online fasting timer is built for people who want a lightweight way to follow common fasting schedules such as 16:8, 18:6, 20:4, or a custom fasting duration without creating an account or downloading an app.

How to Use the Intermittent Fasting Timer

Choose a fasting plan like 16:8, 18:6, 20:4, or enter your own custom fasting hours.
Tap Start Fasting to begin now, or use Start Time to set a past start time if you already began your fast.
Watch your elapsed time, target end time, and live fasting progress update automatically.
Check the body status area for stage guidance as your fasting session moves forward.
Review your fasting history later in the heatmap to see completed sessions by day and year.

Why Use This Fasting Timer

Real-time fasting progress so you always know how much time has passed and how much remains.
Built-in body status guidance that updates as your fasting session progresses.
Support for notifications and browser reminders so you can stay aware of your fasting milestones.
Flexible start-time editing for logging a fast that started earlier.
A history heatmap that helps you review completed fasts and spot patterns over time.

FAQ

Can I customize my fasting hours?

Yes. This intermittent fasting timer includes a custom fasting hours input, so you can set a fasting target that matches your own routine instead of using only preset plans.

What happens if I close the browser?

Your fasting timer data and history are designed to stay available in the same browser on the same device, so you can reopen the page and continue tracking. If you clear browser storage, saved sessions may be removed.

Can I track past fasts?

Yes. You can set a past start time, complete your fast, and review saved sessions in the fasting history and heatmap view.

What devices can use this fasting timer?

You can use this fasting timer on most modern phones, tablets, laptops, and desktop computers with a current web browser. It is designed to work as a browser-based tool, so there is no separate app download required.

How to enable notifications?

Open the timer settings, turn on in-app notifications, and then enable browser notifications if you want alerts from your device. Your browser may ask for permission, and notifications only work after that permission is granted.

Not receiving notifications?

If notifications are not showing up, the fix depends on which type of alert you are using.

In-app notifications:

Make sure in-app notifications are enabled in the timer settings and keep the fasting timer page open in your browser tab. If the page was refreshed or left idle for a long time, try turning the setting off and on again, then start a new test session.

Browser notifications:

Make sure browser notifications are enabled in the timer settings and that your browser has permission to send alerts for this site. If you clicked Block before, reset the site permission in your browser settings and allow notifications again. Also check that your device is not in Focus or Do Not Disturb mode, and test in a modern browser like Chrome, Edge, or Safari.