Most people fast without really knowing what their body is doing, or when to stop. Burn fixes both. It's a fasting timer, weight tracker, and BMI calculator in one simple app — with a notification that tells you the moment your fast is done.
Set up your profile once — age, height, starting weight — and Burn does the rest. Start a fast and a live ring fills toward your goal. Every weigh-in gets logged, your BMI stays current, and a chart shows your trend over time.
Never lose track of your fast Set your fasting goal — anywhere from 12 to 48 hours — and start the timer. Burn shows your projected end time right away, and can send a local notification the second you hit your goal. No more checking the clock every ten minutes. Toggle the alert on or off anytime in Profile.
Track your fast, stage by stage Burn shows exactly where your body is as the fasting hours pass: Fed state → Post-absorptive → Glycogen depletion → Fat burning → Ketosis → Autophagy → Deep autophagy
You'll know when you've cleared your last meal, when glycogen runs low, when you shift into fat burning, when you cross into ketosis, and when a longer fast tips into autophagy — your body's cellular cleanup mode.
What's inside
✔ Live fasting timer with projected end time
✔ Local notification when your fast ends — optional, toggle anytime
✔ Fasting stage tracker — fed state through deep autophagy
✔ Fasting streaks and weekly hour totals
✔ Weight log with full history and trend chart
✔ Automatic lb/kg display — Burn reads your region, no setup
✔ BMI calculator that updates with every weigh-in
✔ Light, Pastel, Dark Blue, and Classic themes
✔ 100% offline — no account, no cloud, your data stays on your device
Why Burn
✔ No subscription — ever. One-time $0.99 purchase.
✔ No ads, no meal plans, no clutter
✔ Private by design — nothing leaves your phone
✔ Built for 16:8, OMAD, extended fasts, or just tracking weight
Whether you're new to intermittent fasting or deep into extended fasts, Burn gives you an honest, real-time view of your progress — and tells you the moment it's time to eat.
Download Burn and start your fasting journey today.
Intermittent fasting, weight & BMI tracker — Fed State to Deep Autophagy.