Understanding cycle phases The 4 phases of your cycle, simply explained
Your cycle is not a black box between two periods. Find out in seconds which phase you are currently in – without an account, without an app, right here.
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What cycle phase am I in?
Cycle length = from the first day of your period to the day before the next one starts. If you don't know it, 28 is the average.
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Overview
The 4 cycle phases at a glance
The day indications refer to an average 28-day cycle. Yours may be shorter or longer – anything between 21 and 35 days is normal. Important: the luteal phase is relatively constant at around 14 days. If your cycle is longer, it is primarily the follicular phase that extends.
| Phase | Days | Hormones | Typical feeling |
|---|---|---|---|
| Menstruation | 1–5 | Estrogen + progesterone low | Fatigue, cramps, withdrawal |
| Follicular phase | 6–12 | Estrogen rises | Energy and motivation return |
| Ovulation | 13–15 | Estrogen peak + LH surge | High energy, peak fertility |
| Luteal phase | 16–28 | Progesterone dominates, then drops | PMS, cravings, water retention |
Menstruation
Day 1–5
Estrogen + progesterone low
Fatigue, cramps, withdrawal
Follicular phase
Day 6–12
Estrogen rises
Energy and motivation return
Ovulation
Day 13–15
Estrogen peak + LH surge
High energy, peak fertility
Luteal phase
Day 16–28
Progesterone dominates, then drops
PMS, cravings, water retention
Phase 1 · Day 1–5
Menstruation
By definition, the cycle begins on the first day of bleeding. Estrogen and progesterone are at their lowest point, the uterine lining is shed – and with it, depending on the intensity of the bleeding, you lose 15–40 mg iron. The fact that you feel tired during these days and prefer retreat over partying is not your imagination, but due to your hormonal state.
What helps now: warmth (also on your plate), iron-rich foods combined with vitamin C, ginger tea for cramps. What you can specifically eat is in our article What to eat during your period? – suitable dishes in 10 recipes for menstruation.
Phase 2 · Day 6–12
Follicular phase
After your period, follicle-stimulating hormone (FSH) takes over: follicles mature in the ovaries, and the strongest one wins. At the same time, estrogen rises steadily – and with it energy, concentration, and often the desire for new things. Many women experience these days as their most productive time.
Your body processes carbohydrates best now (insulin sensitivity is high), and recovery after training is in full swing. You can find suitable foods under Nutrition in the follicular phase, specific dishes in 10 recipes for the follicular phase.
Phase 3 · Day 13–15
Ovulation
The estrogen peak triggers the LH surge, the egg is released – the most fertile time of the cycle. Many feel most energetic and social now. But: Ovulation is not a fixed calendar date. Stress, sleep, and illness can shift it by days – which is why every calculator (including ours) is an estimate, not contraception. You can calculate your predicted ovulation date and fertile window with our ovulation calculator.
Nutritionally, antioxidants and fiber are worthwhile now, as they support the subsequent breakdown of estrogen. More on this: Nutrition in the ovulation phase and 10 recipes for ovulation.
“Ovulation ≈ cycle length minus 14. In a 32-day cycle, it occurs around day 18 – not around day 14.”
Phase 4 · Day 16–28
Luteal phase
After ovulation, the corpus luteum produces progesterone. The basal metabolic rate increases by about 100–300 kcal per day, insulin sensitivity decreases, and when progesterone drops shortly before the period, serotonin also drops – the biochemical explanation for PMS and food cravings.
Magnesium-rich foods, stable blood sugar curves and the permission to eat a little more make this phase significantly more relaxed. To dive deeper: 10 recipes for the luteal phase and Stopping cravings before your period: 8 strategies.
“Cravings in the luteal phase are biochemistry, not a lack of willpower.”
Good to know
If your cycle is not 28 days
The 28-day cycle is an average, not a requirement. Anything between 21 and 35 days is within the normal range, as are slight fluctuations from month to month. Because the luteal phase lasts a fairly constant 14 days or so, the rule of thumb is: Ovulation ≈ cycle length minus 14 – this is exactly how our calculator above works.
Consistently under 21 or over 35 days, sudden strong fluctuations, or very heavy bleeding are a matter for a gynecological practice – not for a blog article.
FAQ
Frequently asked questions about the cycle phases
How do I determine my cycle length?
Count from the first day of your period (= cycle day 1) until the day before the next period begins. This period of time is your cycle length. The value becomes most reliable if you count over two to three cycles and take the average — apps like Bauchgefühl do this automatically.
Which cycle phase comes after the period?
Directly after the period, the follicular phase begins (about day 6 to 12 in a 28-day cycle). Estrogen rises and a follicle continues to mature. Strictly speaking, menstruation itself is already part of the follicular phase – but in everyday life, the separation is more helpful.
Which phase am I in on day 3 of my cycle?
Day 3 is in the menstrual phase – by definition, the cycle begins on the first day of bleeding. Estrogen and progesterone are now at their lowest point, which is why fatigue is completely normal during these days.
How long does each cycle phase last?
In an average 28-day cycle: menstruation approximately days 1–5, follicular phase days 6–12, ovulation around days 13–15, luteal phase days 16–28. Important: The luteal phase is relatively constant at around 14 days – if your cycle is longer or shorter, it is primarily the follicular phase that shifts.
Can my ovulation shift?
Yes, significantly. Stress, lack of sleep, illness, travel, or weight changes can shift ovulation by days. Therefore, every calculation – including ours – is an estimate and not a method of contraception. Those who want to know for sure combine basal body temperature and cervical mucus observation.
What is a normal cycle – are 25 or 35 days okay?
Anything between about 21 and 35 days is considered normal, and slight fluctuations from cycle to cycle are as well. It becomes noticeable if your cycle is permanently shorter than 21 or longer than 35 days, fluctuates suddenly and significantly, or if bleeding becomes unusually heavy – that should be discussed in a gynecological practice.
Should I eat differently in each cycle phase?
Your nutrient requirements actually fluctuate throughout the cycle – the basal metabolic rate increases by about 100–300 kcal in the luteal phase, and you lose iron during menstruation. A balanced basic diet remains the foundation; phase adjustment is the fine-tuning on top. No dogma, no stress.
Note: This page is for general information purposes and does not replace medical advice. The calculator provides an estimate based on average values and is explicitly not a method for contraception or family planning.