Period Tracker & Ovulation Calculator
Predict your next period, fertile window, and ovulation day, and see what each phase of your cycle tends to feel like. Everything is calculated in your browser and never uploaded.
Printable monthly tracker
Add your name, pick a color, mark your days, and print a one-page A4 sheet, filled in or blank.
Eating and moving with your cycle
Here's how food, exercise, and focus can change with each phase.
Rest & renewal
WinterEstrogen and progesterone drop to their lowest point as the uterine lining sheds. Energy is usually lower, so it makes sense to slow down.
Low estrogen · low progesterone
Foods
Iron-rich, warm food helps replace what's lost through bleeding: stewed root vegetables, bone or lentil broths, and dark leafy greens.
Movement & body
Gentle stretching, short walks, or rest are enough. Intense training tends to feel harder than usual this week.
Focus & mood
Lower energy suits quieter work, like journaling or looking back on the past month.
Signs of ovulation
The calculator works from cycle averages. Watching for these signs as well can help you pin down ovulation more precisely.
Transitions from sticky or creamy to clear, slippery, egg-white consistency.
A sustained rise of about 0.3–0.5°F immediately after ovulation has occurred.
A mild ache on one side of the lower belly that some people feel when the egg is released.
Some people notice a stronger sense of smell and a higher sex drive.
Why cycles change
Your cycle responds to what is going on in your life, so the occasional early or late period is usually nothing to worry about.
What causes my period to arrive late or early?
The follicular phase varies in length. Stress, travel, intense training, illness, or changes in diet can delay ovulation, and your next period with it, by several days.
How consistent is the luteal phase?
The luteal phase, after ovulation, tends to stay about the same length for each person, usually 11–14 days.
Does hydration affect menstrual cramps?
It can. Dehydration can intensify prostaglandin-driven uterine contractions, so sipping water or electrolyte-rich fluids may ease cramping for some people.
When should I see a doctor about my cycle?
If your cycles routinely fall outside 21–35 days, bleeding lasts beyond 8 days, or cramping disrupts daily life, it's worth checking in with a gynecologist or reproductive health provider.
For more on how the cycle works phase by phase, see Understanding Your Menstrual Cycle.