The Shed Clock
Your shedding has a timeline. Find out where you are on it.
Most shedding after a shock to the body shows up 2–4 months later and settles over 6–9 months. That's why the cause is often something that happened a season ago, not this week (DermNet).
Build my shed timelineSearch all 43 triggersWhy the delay
At any moment about 85% of scalp follicles are growing and about 15% are resting. A follicle usually grows for about 4 years, then rests for about 4 months. A shock can push as many as 70% of growing hairs into the resting phase at once. They fall out only when new hairs push them out, months later (DermNet). Losing up to about 100 hairs a day is normal.
How the Shed Clock works
- Anchor date. This is the day the trigger happened: a birth, an operation, a first injection, a fever.
- Cited windows. Each trigger's onset, peak and settling window comes from a named label, guideline or study, linked on its page.
- Gaps stay empty. Where no source gives a window, the trigger isn't on the calculator, and the trigger page says so.
Most-searched triggers
GLP-1 medications
Hair loss is listed in the Wegovy (semaglutide 2.4 mg) prescribing information in about 3% of adults versus 1% on placebo…
Life eventsPostpartum
Postpartum shedding is commonly noticed about two months after giving birth…
ProceduresAfter surgery & anaesthesia
Hair shedding after an operation is usually telogen effluvium…
Starting/stopping treatmentsStarting minoxidil
A temporary increase in shedding is commonly reported in the first weeks of minoxidil — the so-called 'dread shed' — and in one 2025 study of topical minoxidil it peaked around week 4 and was below baseline by week 16.…
Life eventsCOVID-19 & high fever
After COVID-19…
Medical treatmentsHair regrowth after chemotherapy
Hair loss from chemotherapy usually starts 1–4 weeks into treatment…
Medications & treatments · Life events & procedures · Full atlas