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Educational Reference & Telemetry

Module Purpose

Obi's Fasting Lab is a free intermittent fasting timer. Pick a time-restricted eating goal such as 16:8, 18:6, 20:4 or OMAD (one meal a day), start the clock, and watch a live ring and stage timeline show roughly where you are in a fast. Stages are typical ranges that vary a lot from person to person, so treat them as a guide, not a measurement. Optional XP, streaks and achievements, plus Obi the fasting coach, keep it fun, and a quiet mode hides all of that if you just want a timer. You can edit start and end times if you forget, add past fasts, view a history chart, and track water with a beaker meter (ounces or milliliters), and export your data as JSON or CSV.

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Obi's Fasting Lab

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Reference Manual & Technical Spec

Obi's Fasting Lab — Overview & Engineering Principles

Obi's Fasting Lab is a free intermittent fasting timer. Pick a time-restricted eating goal such as 16:8, 18:6, 20:4 or OMAD (one meal a day), start the clock, and watch a live ring and stage timeline show roughly where you are in a fast. Stages are typical ranges that vary a lot from person to person, so treat them as a guide, not a measurement. Optional XP, streaks and achievements, plus Obi the fasting coach, keep it fun, and a quiet mode hides all of that if you just want a timer. You can edit start and end times if you forget, add past fasts, view a history chart, and track water with a beaker meter (ounces or milliliters), and export your data as JSON or CSV.

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Zero-Trust Client Execution

Your fasts, goals and settings are saved only in your own browser storage. Nothing is uploaded to a server and there is no account. Download a backup file to move your data to another device or restore it later.

Step-by-Step Operation Guide

  1. Choose a fasting goal. 16:8 is a common starting point.
  2. Tap Start fast. If you forgot to start on time, set the Started at time to when you actually stopped eating.
  3. Watch the ring and stage timeline. Add the goal time to your calendar if you want a reminder.
  4. Tap End fast when you are ready. Ending early is always fine. Break your fast gently with a balanced meal.

Technical Specification Matrix

StorageBrowser localStorage only. Download or upload a JSON backup any time.
Goals1 to 24 hours in the main section. Advanced extended options are hidden by default and capped at 72 hours.
ExportsJSON backup, CSV history, and a calendar reminder file.
MedicalEducational only. Not medical advice.

Frequently Asked Questions & Edge Cases

Can I track water?▼
Yes. Tap the beaker beside the timer to log water in ounces or milliliters and see progress toward a daily goal. Your log stays in your browser. It is educational only, and needs vary, so follow your clinician's advice if you have a medical condition.
Is Obi's Fasting Lab free?▼
Yes. It is free to use, needs no account, and keeps your data in your own browser.
How accurate are the fasting stages?▼
The stages are typical ranges, not measurements. How quickly your body shifts between fuel sources depends on your last meal, diet, activity, health and many other factors.
I forgot to start or end my fast. Can I fix the time?▼
Yes. You can change the start time while a fast is running, set an end time if you forgot to stop, and add or edit past fasts.
Who should not fast without medical advice?▼
Talk to a clinician before fasting if you take glucose-lowering or blood pressure medication, are pregnant or breastfeeding, have a history of disordered eating, are underweight, or have any medical condition. Stop and eat if you feel dizzy, weak or unwell.
Where is my data stored?▼
Only in your browser on your device. Clearing site data removes it, so download a backup if you want to keep it.