periods.day
Understand her cycle
Let her choose what to share
A cycle can offer context, but it cannot explain how she feels. Learn about the phases and ask what support she actually wants.
Open a link she sends or add period days with her agreement. The calendar estimates phases, not emotions.
Cycle length
Period length
Ovulation day
Period days logged: 0 days
Tap every day she bled to add or remove it
01
Use only dates she chooses to share. A private cycle link contains sensitive information; do not forward it without permission.
02
Read the phase tooltips. Premenstrual symptoms can happen before bleeding, but not everyone experiences them the same way.
03
Listen to her experience and offer practical support. Let her decide whether to track symptoms or speak with a clinician.
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A calendar cannot tell you why someone is angry or diagnose PMS. Listen without dismissing her concerns. If symptoms disrupt daily life, support her in seeking care if she wants it. Learn about PMS symptoms and support
You cannot tell from cycle dates. Feelings have many causes and deserve to be heard. Some people experience PMS before a period, but it is not a reason to dismiss what your partner says.
PMS describes symptoms in the weeks before a period. Experiences differ between people and cycles. A calendar cannot diagnose it; recording symptoms over at least two cycles can help a clinician assess a pattern.
Ask, listen and respect her answer. Offer the support she wants, whether that is practical help, space or company. If symptoms affect daily life, encourage access to care without deciding for her.
These estimates use pregnancy data from 221 women who were actively trying for a baby and had stopped using contraception. They recorded each day whether they had intercourse. Li, Wilcox and Dunson (2015, Table 3) used a statistical model to estimate the chance of a clinical pregnancy from one act on a given cycle day. This does not mean the women had sex once every day. The study did not record whether ejaculation occurred inside the vagina. These figures therefore do not estimate the risk with withdrawal. Our calendar shifts the study’s curve to match the calculated ovulation day or the cycle day you set. This is an approximation, not a validated personal prediction. Days before the table starts use its first value. The percentages are population estimates, not your personal odds or a contraceptive method. Li, Wilcox & Dunson (2015)