Hormonal acne calendar
Most period-related acne flares in the week before a period. Enter when your last period started and how long your cycle usually is, and the calendar marks your likely flare weeks for the next three cycles, so you can start spot treatment early instead of being caught off guard.
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Your likely flare weeks
- Cycle 1
Sun, Nov 29, 2026 to Sat, Dec 5, 2026
Week before your period, estimated to start Sun, Dec 6, 2026
- Cycle 2
Sun, Dec 27, 2026 to Sat, Jan 2, 2027
Week before your period, estimated to start Sun, Jan 3, 2027
- Cycle 3
Sun, Jan 24, 2027 to Sat, Jan 30, 2027
Week before your period, estimated to start Sun, Jan 31, 2027
An estimate, not a medical prediction. Cycles vary, so log your real period dates for a few cycles to see your true pattern.
How this tool works
- Your next period start is estimated by adding your average cycle length to the first day of your last period, repeated for three cycles.
- The flare window is the 7 days before each predicted period, the most common timing in a 2014 survey of women with period-related acne.
- Cycles vary, so treat the dates as an estimate. Two or three cycles of tracking show your real pattern.
- Your dates stay in your browser. The calendar file is created on your device.
Sources: Geller et al., J Clin Aesthet Dermatol 2014; Stoll et al., J Am Acad Dermatol 2001
Frequently asked questions
How many days before my period does acne start?
The most common pattern is the week before your period. In a 2014 survey, 56% of women with period-related acne said it got worse in the week before their period.
How common is pre-period acne?
In a 2001 study of 400 women, 44% reported acne flares before their period.
What if my cycle is irregular?
Use your average cycle length and expect the dates to shift. Logging your period for a few cycles gives a better average and shows whether your flares really follow your cycle.
Can I prevent a hormonal breakout?
Keeping up your regular acne treatment through the whole cycle helps, and some people start spot treatment a few days before their usual flare week. Hormonal treatments like combined birth control pills or spironolactone are prescription options to discuss with a doctor.
Do this automatically in the app
Track hormonal acne alongside your menstrual cycle with Acnera. Log your period, scan your skin, and see whether your breakouts follow your cycle.
How Acnera checks this for you