Cycle calendar

When is your next period — and what every day in between means

Enter the first day of your last period and your cycle length. Get a full monthly view — not just one date, but every day color-coded by where you are in your cycle.

First day of your last period

Cycle length (days)

Average is 28, 21–35 is typical

Period length (days)

Date of your last ovulation (if you know it — optional)

Sharpens the prediction. Leave it blank and we’ll estimate from your cycle length.

This is an estimate based on average cycle patterns, not a birth control method. Accuracy may be lower with irregular cycles.

Period

Highly fertile

Transition days

Low probability

Next period

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Estimated ovulation

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Colors are based on average cycle-phase lengths, not your personal hormone data. Fertility-awareness methods carry a real failure rate even when used carefully — if you’re relying on this for pregnancy planning or prevention, pair it with another method or talk to a doctor.