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 间歇性断食计时器

免费的 16:8 间歇性断食倒计时器。输入上次进食时间，实时追踪断食与进食窗口——无需注册，100% 本地运算。

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.

Related health tools

Macro Split Calculator — divide daily calories into protein, carbs, and fat grams
BMR Calculator — find your baseline daily calorie requirement
Sleep Cycle Calculator — align your bedtime with 90-minute sleep cycles
Water Intake Calculator — daily hydration target by weight and activity
Calorie Burn — Walking — estimate calories burned on a walk

常见问题

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

反馈这个工具的问题