Calculadora de Menstruação Online Grátis
Adaptive cycle prediction with ovulation window, fertile days, phase visualization, irregular cycle detection & health insights
This period and cycle calculator predicts future menstrual periods, identifies your ovulation window and fertile days, and visualizes each phase of your cycle. It adapts to irregular cycles by analyzing your actual cycle history — giving more accurate predictions for those whose cycles don't conform to the textbook 28-day model.
Frequently Asked Questions
Sobre Esta Calculadora
The menstrual cycle is regulated by a complex interplay of hormones — estrogen, progesterone, FSH, and LH — that orchestrate follicle development, ovulation, and either implantation preparation or shedding of the uterine lining. Understanding your cycle phases gives you useful information for fertility planning, recognizing hormonal patterns, and monitoring changes that might warrant medical attention.
Cycle length varies naturally from person to person and from cycle to cycle. A normal range is 21–35 days, with most variation occurring in the follicular phase (before ovulation). The luteal phase — from ovulation to the next period — is remarkably consistent at approximately 14 days across most individuals.
Tracking three or more cycles provides enough data to calculate your personal average and identify irregularities. Cycles consistently outside the 21–35 day range, or periods that are unusually heavy or painful, are worth discussing with a healthcare provider.
Prevê suas futuras menstruações, identifica a ovulação e os dias férteis.
Exemplo Resolvido
Predicting next period and fertile window for a 30-day average cycle
Entradas:
- Last period start: April 5, 2025
- Average cycle length: 30 days
- Average period duration: 5 days
Passo a Passo:
- Next period start: April 5 + 30 days = May 5, 2025
- Ovulation estimate: May 5 − 14 days = April 21, 2025
- Fertile window: April 16–22 (ovulation day −5 to +1)
- Follicular phase: April 10 – April 20 (post-menstruation to ovulation)
- Luteal phase: April 22 – May 4 (post-ovulation to next period)
Dicas
- Cycle length varies naturally 21–35 days. 28 days is the statistical average, not the rule.
- Tracking 3+ past cycles lets the engine personalize your fertile window prediction.
- Ovulation usually occurs 14 days BEFORE your next period — not 14 days after your last one.