Fasting Timer
Track your fast in real time. See exactly which metabolic phase you're in — from fat burning to ketosis to autophagy.
Fasting goal
16:00:00 until 16h goal
Current phase: Fed state
0–4 hours
Your body is digesting and absorbing nutrients. Insulin is elevated.
Fasting phases
Fed state
0–4hYou are hereYour body is digesting and absorbing nutrients. Insulin is elevated.
Early fast
4–8hBlood glucose normalising. Glycogen stores beginning to deplete. Insulin falling.
Fat burning begins
8–12hGlycogen stores depleting. Body increasingly burning fat for fuel. Glucagon rising.
Ketosis entry
12–16hLiver begins producing ketones. Fat oxidation accelerating. Mental clarity often improves.
Deep fat burning
16–24hSignificant ketone production. Growth hormone rising. Cellular repair processes activating.
Autophagy
24–48hCellular autophagy (self-cleaning) significantly elevated. Old, damaged cells being recycled. Anti-aging effects.
Extended fast
48–72+hDeep autophagy. Stem cell regeneration beginning. Significant immune system reset. Medical supervision recommended.
Phase timings are approximate and vary by individual. Extended fasts (36h+) should be undertaken with medical supervision.