Intermittent Fast Timer.

Start a fasting timer and track how many hours and minutes you've been fasting. Stop anytime to see your total fasting duration.

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Click Start Fast to begin tracking

Track your intermittent fasting sessions with a simple start/stop timer. Click start to begin tracking your fast — the timer stores your start time in your browser and shows elapsed hours and minutes in real-time. When you're ready to eat, click stop to see a summary of your total fasting duration. All data stays on your device.

How to use

Click Start Fast to begin tracking your fasting session. The timer will show how many hours and minutes you've been fasting. When you're ready to eat, click End Fast to see a summary of your total fasting duration. Your start time is saved in your browser so you can close the page and come back.

An intermittent-fast timer is useful when the main question is simply how long the fast has actually lasted

That sounds basic, but it solves a real habit problem. People often remember roughly when they stopped eating, then gradually turn “roughly” into a false sense of precision. A fasting timer is valuable because it replaces memory with an exact elapsed duration.

This tool is best for simple self-tracking when you want to know where the current fast stands right now.

Where it helps most

Daily fasting routines

If you are following a repeated pattern like 12, 14, or 16 hours, the timer makes the window visible instead of approximate.

Consistency checks

A timer is useful when the goal is not only to fast, but to know whether you actually hit the intended duration.

Lightweight habit tracking

Some people do not want a full nutrition app when the only question is the elapsed time.

What makes the timer useful

Its value is precision without overhead. You start the session, let it run, and return to a live answer rather than an estimate from memory.

That makes it especially helpful for repeated habits, where small differences in start and end times accumulate into a less reliable picture than people think.

Common mistakes in fasting tracking

Starting from the wrong moment

If the timer begins well after the last meaningful intake, the precision is false from the start.

Ending on the planned time instead of the real break-fast moment

A timer is only honest if the stop point reflects what actually happened.

Treating duration as the whole story

Elapsed hours may be the metric you want here, but they do not automatically say anything about whether the approach is suitable, healthy, or effective for a specific person.

Practical examples

Checking whether a target was met

A 16-hour fast either happened or it did not. The timer removes the ambiguity.

Comparing routine patterns

If you are testing several fasting lengths, a consistent timing method makes the comparison cleaner.

Keeping the process lightweight

For many users, the timer is enough because they are not trying to log food, macros, or biomarkers in the same place.

What this tool does not do

This tool measures fasting duration. It does not recommend a fasting protocol, give medical advice, or assess calories, hydration, medication timing, or health outcomes. It is a timer, not a clinical or nutrition system.

Why it remains useful

Habit tools often earn their value by making one narrow thing visible and exact. For intermittent fasting, elapsed time is often that thing. A simple timer helps because it makes the habit measurable without adding unnecessary system overhead.

Examples

Quick start Click Start Fast → timer begins counting immediately
16-hour fast Start at 8pm, end at 12pm next day = 16 hours 0 minutes
Browser persistence Close the page and return later — timer continues from saved start time

FAQ

Does this work if I close the browser?

Yes. Your start time is saved in your browser's local storage, so you can close the page and come back later — the timer will continue from where you left off.

How long should I fast?

Common intermittent fasting schedules include 16:8 (16 hours fasting, 8 hours eating window), 18:6, or 20:4. Consult a healthcare professional for advice suitable for you.

Is my data sent anywhere?

No. All data is stored locally in your browser. Nothing is sent to any server.

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Privacy and data handling

This tool runs entirely in your browser. Nothing you type or paste is sent to any server — all processing happens locally on your device.