Health & Fitness Calculators
Ovulation Calculator


Ovulation Calculator

Not sure when you’re ovulating? Use this free ovulation calculator to estimate your most fertile days and know when you are most likely to conceive.

Ovulation Window Jun 13, 2023 - Jun 17, 2023
Most Probable Ovulation Date Jun 15, 2023
Intercourse Window for Pregnancy Jun 10, 2023 - Jun 17, 2023
Pregnancy Test Jun 24, 2023
Next Period Start Jun 29, 2023

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ESTIMATIONS FOR THE NEXT 6 CYCLES
Period Start Ovulation Window Due Date
1 Jun 1, 2023 Jun 13, 2023 - Jun 17, 2023 Marc 7, 2024
2 Jun 29, 2023 Jul 11, 2023 - Jul 15, 2023 Apr 4, 2024
3 Jul 27, 2023 Aug 8, 2023 - Aug 12, 2023 May 2, 2024
4 Aug 24, 2023 Sep 5, 2023 - Sep 9, 2023 May 30, 2024
5 Sep 21, 2023 Oct 3, 2023 - Oct 7, 2023 Jun 27, 2024
6 Oct 19, 2023 Oct 31, 2023 - Nov 4, 2023 Jul 25, 2024

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Table of Contents

  1. The Ovulation Process
  2. Ovulation Symptoms
  3. Hormonal Changes During Ovulation
  4. When To Expect Ovulation
  5. Tools for Tracking Ovulation
    1. Determining the day of ovulation by temperature change
  6. Ovulation is Essential for Getting Pregnant
  7. Multiple Ovulations During The Same Cycle
  8. Female Infertility and Inability to Ovulate
    1. PCOS (Polycystic Ovary Syndrome)
    2. Primary Ovarian Insufficiency
    3. Hypothalamic Dysfunction
    4. Prolactin Excess
    5. Another Common Causes

Ovulation Calculator

As a woman, you've probably heard the term "ovulation" a lot. But what does it mean? Ovulation occurs during your menstrual cycle when an ovary releases an egg. Though an egg is released, it may or may not get fertilized by sperm. If it is fertilized, the egg will travel to the uterus, where it will implant and create a pregnancy. However, if the egg does not become fertilized, it begins to disintegrate, the lining of the uterus will shed, and lead to menstruation.

Understanding this process is vital to helping women prevent or achieve pregnancy. Following your cycle may also help diagnose some medical conditions. Ovulation Calculators Help Track This Cycle.

If you're trying to conceive, the process will be much easier if you know what days of the month you are most fertile. Consider that the average woman's monthly cycle is about 28 days, though it can differ among women. Of these 28 days, there are only six on average when a woman can get pregnant. This is known as the "fertile window."

The free ovulation calculator estimates when you can expect your fertile window to occur. Remember that the calculator is meant to give you a rough estimate; there's no guarantee you will become pregnant.

The truth is that with a timeframe of only six days, there's a good chance you'll miss your window. So, rather than losing the opportunity to become pregnant, use the fertility window calculator to determine what days you should try.

The Ovulation Process

A woman's menstrual cycle starts on the first day of her period, which is the beginning of the follicular phase. During this phase, the pituitary gland releases follicle-stimulating hormone (FSH), which encourages the growth of ovarian follicles, each containing an egg. As one egg becomes dominant and fully mature, a surge of luteinizing hormone (LH) triggers ovulation.

Ovulation typically occurs about 10 to 16 days before the start of the next menstrual period, but this can vary widely among women and from cycle to cycle. The subsequent luteal phase ensues, during which the body prepares for a potential pregnancy. If fertilization does not occur, the corpus luteum (the leftover follicle after the egg is released) degenerates, leading to a drop in progesterone and estrogen, and the uterine lining is shed during menstruation. However, if a pregnancy is established, these hormone levels remain elevated to sustain the uterine lining.

Each woman’s cycle is unique, with the average cycle length ranging from about 25 to 35 days. The cycle's consistency may also vary, with some women experiencing shorter or longer cycles. The process is a complex orchestration of hormones and physiological responses that restart with each menstrual period.

Ovulation Symptoms

There are seven primary ovulation symptoms to watch for, including:

  • swollen vagina or vulva,
  • basal body temperature decreases and then rises again,
  • increased sex drive,
  • a soft, open cervix,
  • light skin spotting,
  • minor cramping or tingling in lower abdomen,
  • cervical mucus becomes thinner, more transparent, and resembles egg whites.

Hormonal Changes During Ovulation

The ovaries' primary functions are to produce eggs and hormones. When a woman is born, she has several million immature eggs in her ovaries, but does not generate more in her life.

The eggs are constantly changing. Many of them die before reaching maturity. Oocyte loss occurs constantly: before birth, during puberty, and even while taking birth control. Essentially, the ovary experiences a constant state of decreased egg count throughout its life.

A woman's reproductive aging comes before her physiological old age. It is caused by a decrease in the number of germ cells. The woman-to-be has the maximum number of germ cells while she is in the womb at 20–22 weeks of pregnancy. Their number may reach 7 million, and all of them are at different stages of development.

By the time she is born, the woman-to-be has about 2 million oocytes. By the time a woman has her period, only 250,000–450,000 follicles are left.

By the age of 35, about 25,000 follicles remain in a woman's ovaries.

During puberty, the increase in lutein hormone (LH) and follicle-stimulating hormone (FSH) causes eggs to start maturing, and fluid begins building around each of them.

As we mentioned, the first day of menses is known as the first day of your cycle. During this phase, estrogen levels are lower, which signals an increased release of LH and FSH. These hormones work to stimulate the growth of ovarian follicles, each of which contains an egg.

The number of follicles maturing each month varies by woman, but one will begin to grow faster than the others. It becomes known as the dominant follicle.

By day seven of the cycle, the follicle continues to grow as blood levels of estrogen start to increase. Increased estrogen levels inhibit the secretion of follicle-stimulating hormone, which causes small follicles to die off.

When estrogen levels are high enough, the body triggers the release of LH, which is usually on day 13 of your cycle. The peak in LH triggers a complicated chain of events inside the follicles, resulting in the egg's final maturation. Roughly 28 to 36 hours after the surge in LH, ovulation will occur.

All cells remaining in the ovarian follicle begin a transformation in which they become the corpus luteum. And along with estrogen, the body also begins producing progesterone to prep the uterus for implantation of a fertilized egg.

When the second half of your monthly cycle begins, it's called the luteal phase. This stage starts when you ovulate and typically lasts between 10 and 15 days.

During this time, the body changes to support the embryo in the case of pregnancy. These changes are brought on by the increase in progesterone, which is made in the corpus luteum. When this hormone is present, the uterus starts to build a vascularized bed for the egg.

If pregnancy is achieved, the corpus luteum releases progesterone until about ten weeks into the pregnancy. If an embryo does not implant, the progesterone levels will begin to decline as the corpus luteum and lining of the uterus are shed.

When To Expect Ovulation

Ovulation usually occurs around 14 days into your monthly menstrual cycle. So, once your monthly period begins, ovulation should occur roughly two weeks from that day.

Tools for Tracking Ovulation

As we said before, the ovulation calculator is the easiest tool to use to track ovulation. But there are more accurate ways to determine ovulation:

  • Folliculometry (this is the most accurate objective method).
  • Ovulation tests. They are based on determining the increase in LH hormone levels approximately one day before ovulation. However, false-positive results are not ruled out during this type of testing.
  • Measuring the basal temperature. You can use the temperature graph to determine if and when ovulation has occurred.
  • Blood tests. To confirm ovulation, your doctor may prescribe a blood test for the hormone progesterone, whose blood concentration rises around day 7 after ovulation.

Determining the day of ovulation by temperature change

A person's body temperature changes throughout the day. This temperature is called the basal temperature. It reaches its lowest point during nighttime sleep. According to the temperature dynamics, you can see the signs of ovulation in a woman.

During the first few days of the menstrual cycle, the basal temperature stays approximately the same. The day before ovulation, it drops by a fraction of a degree. And on the day of ovulation, the basal temperature rises above the level of the beginning of the cycle. All these jumps are barely noticeable. The temperature after ovulation is only 0.3-0.6 degrees above the temperature before ovulation. But you can recognize these signs due to the characteristic pattern of changes.

It is essential to follow the rules for the method to work:

  • Only a very accurate thermometer is suitable for measuring the temperature. A woman needs to track changes in tenths of a degree.
  • You should take measurements immediately after waking up, without getting out of bed. Even if the woman quickly runs to her locker for a thermometer before measuring, her basal temperature will rise.
  • To achieve the necessary accuracy, measuring at about the same time of the day is desirable. Before this, the woman should have at least three hours of restful sleep without waking up.
  • Measurements are taken rectally. Other methods can give significant deviations from the actual basal temperature.
  • The temperature method of finding signs of ovulation is only suitable for disciplined women with a clear daily routine. But even they can sometimes see unexpected peaks on the graph. The results of measurements are affected not only by the phase of the menstrual cycle, but also by various side factors. The basal temperature can rise due to malaise, lack of sleep, stress, or having sex the night before. This can make it difficult to determine the day of ovulation.

Ovulation is Essential for Getting Pregnant

If you are trying to conceive, and you have a regular menstrual cycle, the ideal time for sex is the day before ovulation. However, your chances are also pretty high if you have sex during the five days leading up to ovulation and the day of ovulation.

Essentially, you want to know when ovulation will occur, so you can have more sex during that fertile window to get pregnant. Increased intercourse means more sperm, and since the quality of sperm has a short life, it is better to get it when it can fulfill its function.

In addition, determining your ovulation window will tell you when to reduce the amount of sex you have if you do not want to become pregnant. So, in general, tracking ovulation using a free ovulation calculator is worth it for every woman.

Multiple Ovulations During The Same Cycle

Some women falsely believe that you can ovulate twice during the same cycle. However, it doesn't work like this. Ovulation can only occur once during a cycle. What women are mixing up is the fact that you can release multiple eggs during the same cycle.

If you release more than one egg, it increases the risk that you'll conceive fraternal twins if more than one egg is fertilized. But a woman cannot release two eggs at different times in the same cycle.

Female Infertility and Inability to Ovulate

Unfortunately, not every woman can ovulate. And lack of ovulation leads to infertility. Underlying issues with the body's release of hormones by the pituitary gland or other problems in the ovary can lead to ovulation disorders, such as:

PCOS (Polycystic Ovary Syndrome)

This condition causes a hormonal imbalance that interferes with ovulation. It's associated with obesity, insulin resistance, acne, and abnormal hair growth on the body or face. This is the most common cause of ovulation problems in women.

Primary Ovarian Insufficiency

This disease is also known as premature ovarian failure and is commonly caused by the ovary prematurely losing eggs or an autoimmune response. This can be caused by undergoing chemotherapy or may be due to genetics.

Hypothalamic Dysfunction

We previously discussed the importance of two hormones, LH and FSH, and how they relate to pregnancy and your monthly cycle. This condition occurs when the production of these hormones is disrupted. The most common symptoms are absent or irregular periods. It can be brought on by extreme weight loss or gain, excess emotional or physical stress, and having a body weight that's too low or high.

Prolactin Excess

This can be caused by certain medications and occurs when the pituitary gland begins creating too much prolactin. The increase of this hormone lowers estrogen production and can lead to infertility.

Another Common Causes

While those are among the most common conditions that lead to infertility and ovulation problems, other conditions can also cause them. Other risk factors include damaged fallopian tubes, pelvic inflammatory disease, endometriosis, and other cervical or uterine issues.