Ovulation & Fertile Window Calculator
Know your most fertile days, expected ovulation date and next period — planned around your own cycle, reviewed by our gynaecologists.
The day your bleeding started
From day 1 of one period to day 1 of the next
How many days you usually bleed
Estimates are based on a typical luteal phase of 14 days. Results are for guidance only.
Understanding your cycle
The four phases of your cycle
Day 1–5
Menstrual
The uterine lining sheds. Hormone levels are at their lowest and energy may dip.
Day 1–14
Follicular
Oestrogen rises and follicles mature in the ovaries, preparing an egg for release.
Around day 15
Ovulation
A mature egg is released and lives for 12–24 hours. This is your peak fertility.
Day 16–28
Luteal
Progesterone rises to support a possible pregnancy; PMS symptoms may appear.
Listen to your body
Signs you may be ovulating
A calculator gives you the estimate; your body gives you the confirmation. Watching for these natural signs alongside the calendar makes your prediction far more reliable.
Explore our gynaecology servicesCervical mucus changes
Clear, stretchy, egg-white-like discharge signals peak fertility.
Rise in basal body temperature
A small rise of 0.3–0.6°C after ovulation, seen with daily morning tracking.
Mild pelvic twinge
Some women feel a light one-sided ache (mittelschmerz) around ovulation.
Increased libido & energy
Hormonal shifts can bring a natural boost in mood and desire mid-cycle.
Good to know
Frequently asked questions
Ovulation usually happens about 14 days before your next period starts. The calculator takes the first day of your last period, adds your average cycle length, and counts back 14 days to estimate your ovulation day.
This tool provides estimates only and is not a substitute for medical advice or a contraceptive method. Please consult a Stepcare gynaecologist for personalised guidance.