Ovulation Calculator

Use this online ovulation calculator that helps you to find the most fertile days and exact ovulation date to increase your chance of conceiving. Remember that a woman can only get pregnant during her ovulation cycle.

Enter first day of your last period

Average Length of Cycles (Days)

Created By:

Emily Smith
Emily Smith

Emily Smith

Emily holds a Bachelor's degree in Computer Science from a renowned university. She continued her education with specialized courses in mathematics and data analytics.

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Verified By:



Adam holds a Master's degree in Public Health with a focus on reproductive health and epidemiology.Adam has worked closely with healthcare providers and policymakers to develop evidence-based strategies.

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Based on Research By: Wilcox AJ, Dunson D, Baird DD. Fertile Window TimeBMJ;

Note: The product on this page can provide estimations only due to the change in the length of the menstrual cycle. The results can not replace medical advice by a Doctor.

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The ovulation calculator quickly estimates your fertility window and the date when you are most fertile based on your regular menstrual cycle length. It uses the first day of your last period and the length of your cycle to calculate ovulation and the fertility calendar. With that, explore important dates for the next six months that will help you get pregnant fast.

Working of Our Ovulation Calculator:

The ovulation date calculator functions to predict ovulation date within the next fertility calendar window. It requires basic information that includes:

What You Need To Enter?

  • Enter the 1st date of your last menstrual cycle
  • Now enter the average length of your menstrual cycle
  • Enter the luteal phase if you want (The fertile days calculator considers your luteal phase around 14 days)

What Will You Get?

  • Ovulation Date
  • Ovulation calendar for the next six months cycles
  • Next period date
  • A safe period in which conception is least likely to occur
  • Expected due dates w.r.t intercourse on any of the next fertility windows
  • Pregnancy test (when you need to visit MEDICAL PRO)

What Is Ovulation?

“Your ovulation date is a day when any of your two ovaries releases a mature egg into the fallopian tube. This egg is ready for fertilization and if it meets the male sperm, the conception journey begins here”

When the egg is liberated from your ovary, it may or may not be fertilized by sperm. If the egg is fertilized, it may travel to the uterus, build an embryo, and implant to develop into a baby.

On the other hand, if it remains unfertilized, then it dissolves and the uterine lining is shed during the period.

If your period cycle comprises of same length every month, then our best period and the free ovulation tracker automatically tracks your next six fertility window and ovulation dates based on the first days of your last period.

What Happens During Ovulation?

  • Egg Maturation: Inside ovaries, there are many follicles that contain immature cells. Out of these, only one gets mature.
  • Luteinizing Hormone (LH) Surge: During ovulation, this particular hormone increases its level and lets the egg flow into the tube.
  • Egg & Sperm Meetup: When the mature egg combines with the male sperm in the fallopian tube, the ovulation starts. This is how the pregnancy starts!

When Do You Ovulate?

Ovulation may or may not happen on the same date every month. It depends upon the length of the menstrual cycle which can be as minimum as 22 and as maximum as 40.

If the length of your menstrual cycle is typical (28 days), then you are most likely to ovulate at least 14 days before the next period starts. Also, it happens for about 16 - 32 hours during which the chances of pregnancy are at peak if you experience any intercourse.

But the length of the menstrual cycle may vary and due to this, the gap between the ovulate date and the next period can also change.

This is why if you have irregular cycle length, you should consult with a medical expert to predict your fertility calendar and ovulation date. You can also do that by ovulation calculator girl which provides you with the best possible dates of the ovulation calendar based on your menstruation.

How To Get Pregnant Fast? - Important Tips

  • You should have intercourse every other day during your fertility window after you calculate it with this fertility calculator
  • You should maintain your weight because women with extra or less weight are more likely to face ovulation disorders
  • Try taking prenatal vitamins at least one month before you try. Take this vitamin with folic acid
  • Visit your doctor regularly so that you may plan to manage any complications before or during pregnancy
  • Eat a healthy diet enriched in macros. Exercise regularly to maintain a caloric balance

Signs of Ovulation

You might be thinking how could I feel if I am ovulating? Well, ovulation has clear indications that might assist you in knowing if you are experiencing it or not. These include:

Increase In Basal Body Temperature:

When ovary releases an egg, the level of the progesterone hormone increases. This increase is directly proportional to the basal body temperature. So whenever you feel a rise in your body heat, it might be an indication that you are ovulation. But still, it is just a rough estimation.

Change In Cervical Mucus:

The nature of cervical mucus becomes slippery and stretchy during the fertility calendar. It is maximum on the exact day of ovulation.

Ovulation Pain:

You may feel mittelschmerz, which is a slight pain felt in the lower abdomen part of the body.

Libido Boost:

This is another clear sign of ovulation. Your sex drive may increase during the ovulation and you will mostly feel.

Nausea and Headaches:

Your Estrogen and Progesterone levels arise causing severe Nausea and headaches.

Breast Tenderness:

Most often, women may feel tenderness in breasts with sore nipples during the ovulation window.

Changing In Mood:

You may feel happier when ovulation occurs.

Heightened Sense of Smell:

It is a common yet important symptom of ovulation. Most of the time during pregnancy, the sense of smell is automatically heightened, making you feel the aroma of anything more than normal.

If you experience these signs, you must quickly figure out your ovulation date with the ovulation predictor. If the tool gives you the date around when you feel these symptoms, you are perfectly ovulating then.

signs of ovulation

How Does Your Menstrual Cycle Work?

The following information is intended for a cycle length of 28 days, which is considered normal. However, if your cycle length changes between 21-40 days, the information still holds true for you.

  • Remember that a menstrual cycle starts on the first day of your period and ends on the first day of the next period
  • In a regular cycle, the ovulation happens at the same time you can also predict with this smart ovulation tracker and plan your pregnancy accordingly
  • When you are ovulating, your cervical mucus becomes stretchy and thinner. This allows the male sperm to flow toward the released egg inside the fallopian tube
  • If the egg meets up with sperm cells, it gets fertilized
  • If the egg is not fertilized, then the body re-absorbs it back and the womb lining is shed
  • This lining is secreted from the body in the form of thick blood wastage which we consider a period
Menstrual Cycle

Frequently Asked Questions

In What Ways I Can Improve My Chances of Conceiving Naturally?

You should eat foods that are enriched in antioxidants, avoid trans fats & caffeine, quit smoking and alcoholic consumption, and eat more fiber daily. With that, taking supplements and multivitamins can also help you conceive naturally.

Furthermore, having sex near the time of ovulation also increases the chances of natural conception.

When Do I Ovulate If My Cycle Is 40 Days?

Women with regular menstrual cycles normally have periods every 21-35 days. Well, if your menstrual cycles last 35 days or longer The menstrual cycle is disturbed by different habits, then you might be ovulating on day 21 or later.

Furthermore, using this ovulation calculator will also assist you in determining your ovulating time concerning the 40-day cycle.

What Are The Signs of Irregular Ovulation?

If you have irregular cycle lengths, missing periods, changes in mood and body weight, etc., then you are experiencing irregular ovulation.

The most prominent of all is non-uniform or absence of menstrual cycle. Some secondary signs include Polycystic ovary syndrome, Hypothalamic amenorrhea, Premature ovarian failure & menopause, and Hormone imbalances.

What Is The Fertile Window?

In the menstrual cycle, a fertile window is a period of days during which pregnancy chances are at peak.

Usually, the fertile window consists of five days prior to ovulation, ovulation day, and the upcoming day after it. For most people, the fertility window exists between 11 to 21 days of the menstrual cycle. But it can vary from one woman to another.