What is 16:8 intermittent fasting?

16:8 intermittent fasting means eating during an 8-hour window (for example, noon to 8 PM) and fasting for the remaining 16 hours. No calorie counting is required — the restriction is purely on timing.

Is this fasting timer free with no signup?

Yes. The timer is completely free, requires no account, and runs entirely inside your browser. Your last meal time is saved locally — nothing is sent to any server.

Does my data leave my device?

No. All calculations and timer logic run in JavaScript inside your browser. Your last meal time is stored only in localStorage on your own device.

Does it work on mobile?

Yes. The timer is mobile-first and works on iPhone Safari and Android Chrome. Add it to your home screen (Share → Add to Home Screen on iOS) for instant access like a native app.

What can I drink during the 16-hour fasting window?

Water, black coffee, and plain tea are generally accepted during a fast. Avoid anything with calories, sugar, or milk — these can trigger an insulin response and break the fast.

What should I eat during the 8-hour eating window?

There are no strict rules, but most people see better results with whole foods, adequate protein (0.7–1 g per lb of body weight), and moderate carbohydrates. Use the Macro Split Calculator to set your protein, carb, and fat targets.

16:8 Intermittent Fasting Timer

Free live countdown timer for 16:8 intermittent fasting. Set your last meal time and track your fasting and eating windows — no signup, no app, 100% private.

100% client-side · no upload · no signup

When did you last eat?

Enter the time your last meal or eating window ended.

How to use

Enter the date and time you finished your last meal (the end of your eating window).
Click Start Timer — your 16-hour fasting countdown and 8-hour eating window appear instantly.
Bookmark this page; your last meal time is saved in your browser and reloads automatically next visit.

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Calorie Burn — Walking — estimate calories burned on a walk

Frequently Asked Questions

What is 16:8 intermittent fasting?: 16:8 intermittent fasting means eating during an 8-hour window (for example, noon to 8 PM) and fasting for the remaining 16 hours. No calorie counting is required — the restriction is purely on timing.
Is this fasting timer free with no signup?: Yes. The timer is completely free, requires no account, and runs entirely inside your browser. Your last meal time is saved locally — nothing is sent to any server.
Does my data leave my device?: No. All calculations and timer logic run in JavaScript inside your browser. Your last meal time is stored only in localStorage on your own device.
Does it work on mobile?: Yes. The timer is mobile-first and works on iPhone Safari and Android Chrome. Add it to your home screen (Share → Add to Home Screen on iOS) for instant access like a native app.
What can I drink during the 16-hour fasting window?: Water, black coffee, and plain tea are generally accepted during a fast. Avoid anything with calories, sugar, or milk — these can trigger an insulin response and break the fast.
What should I eat during the 8-hour eating window?: There are no strict rules, but most people see better results with whole foods, adequate protein (0.7–1 g per lb of body weight), and moderate carbohydrates. Use the Macro Split Calculator to set your protein, carb, and fat targets.

Last updated: 2026-05-20 By jarvisbox

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