Home / Health Calculators / Ovulation Calculator

    Ovulation Calculator

    First Day of Your Last Period


    Average Length of Cycles:

    28 Days

















    Overview -

    Ovulation Calculator

    Since ovulation period is the best time to get pregnant, many women use ovulation calculators to help them conceive. These calculators are also known as ‘best time to get pregnant calculators. People who are planning to have children can attempt conceiving during the most fertile window to increase their chances of success. In addition to this, ovulation day calculators can be helpful in predicting the energy levels and help with planning major events accordingly. Hormones in a woman’s body fluctuate throughout her menstrual cycle, which can impact her mood, productivity, and overall health.

    Here, you will learn about the ovulation day calculator with some examples to help you understand the calculator better.


    Menstrual Cycle, Ovulation, and Conception

    Women have an average menstruation cycle of about 28 days, which starts when they hit puberty and continues to repeat till menopause. Your menstruation cycle starts on the first day of your period; this cycle may repeat every 22 to 40 days. One (or more) egg from alternate ovaries (females usually have two) matures in a cycle and waits for fertilisation inside the uterus; this process is called ovulation.

    During the ovulation period, which lasts about 6 days, your body is most susceptible to become pregnant. The mucus in your cervix, which is like a gateway to the uterus, starts to become thinner to allow easy entry of the sperms through the vagina. Since the lifespan of a sperm is up to 5 days, having sex around your ovulation cycle increases the chances of you getting pregnant. If the egg is not fertilised by the end of your menstruation cycle, the body prepares to remove it from the uterus along with the plush endometrial lining (in which the fertilised egg would have been implanted); this process is your period.

    The menstrual cycle of a woman plays an important role and influences the everyday life of that woman. The hormones in a female’s body fluctuate during the menstrual cycle, which impacts her performance, mood, and overall health. As you know the length of this cycle may vary from person to person; hence, many women prefer to use an ovulation period calculator.

    What is an Ovulation Calculator?

    An ovulation calculator is a simple tool that helps in the calculation of fertile days for a particular menstrual cycle. The accuracy of an ovulation calculator may be off sometimes, but most of the times you can determine the ovulation day or date with the help of this simple calculator.

    Your fertile window—the best time to get pregnant—starts on the 20th day (on average) of your menstruation cycle and lasts for up to 6 days. If this is not your typical ovulation cycle, chances are you may still be able to conceive as the fertile window is of about 6 days; if you include the lifespan of the sperm, it gives you a pretty good chance of conceiving.

    Here’s a simple formula to calculate the ovulation day:

    First day of the fertile window = (Number of days in your menstrual cycle) − 20 (average ovulation cycle) + (First day of the last period)

    For example, if you started your period on 5th February and your menstruation cycle is 26 days long, then the first day of your fertile window will be:

    24 − 20 + 5 = 11, i.e., 11th February

    Since the fertile window is usually 6-day long, 11th to 17th February will be your intercourse window for pregnancy.

    *Approximate ovulation date is the last day of the fertile window, which is 17th February in the above-mentioned example.

    Let’s assume you started your period on 24th April and your menstruation cycle is 30 days long, then the first day of your fertile window will be:

    30 − 20 + 24 = 34, i.e., 4 days after 30th April or 4th May

    The fertile window will be from 4th to 10th May, and 10th May will be the approximate ovulation date.

    You can use this simple ovulation date calculator to find the day of ovulation and the fertile window, but there is no such thing as ‘100 percent accurate ovulation calculator’ because many factors affect the ovulation. Please note if you are having any trouble conceiving, it is better to consult a gynaecologist.


    Other Calculator

    Calculate as per your need

    BMR Calculatorimage

    BMR Calculator

    Focused on shedding weight the healthy way! Use BMR Calculator to know the number of calories to cut out on a daily basis

    GFR Calculatorimage

    GFR Calculator

    Concerned with your kidney health! Use a GFR Calculator, one of the best indicators of kidney function

    Carb Calculatorimage

    Carb Calculator

    Watching what you eat to achieve your fitness goals! Use Carb Calculator to track and manage your carbohydrate intake

    Body Fat Calculatorimage

    Body Fat Calculator

    Feeling overweight! Use Body Fat calculator, an extremely convenient method that does not need special equipment

    Ideal Body Weight Calculatorimage

    Ideal Body Weight Calculator

    Want to know the right weight for your Height! Use Ideal body Weight calculator to know what’s the healthy weight as per your height

    BMI Calculatorimage

    BMI Calculator

    Are you underweight or overweight! Use BMI Calculator to find out the optimal weight with respect to your height

    Period Calculatorimage

    Period Calculator

    Want to predict your menstrual cycle! Use Period Calculator to help you know your next period date

    Pregnancy Calculatorimage

    Pregnancy Calculator

    Planning a family! Use Pregnancy Calculator to know what stage of pregnancy you are and your estimated due date

    Protein Calculatorimage

    Protein Calculator

    Want to know how much protein to consume daily! Use Protein Calculator to find out how much protein is recommended for daily intake

    TDEE Calculatorimage

    TDEE Calculator

    Want to manage weight as per your health goals! Use TDEE Calculator to know how much energy is burned during a day

    Ovulation Calculator FAQ'S




    One Place for All Your Health Needs


    Doctor Consultations


    Lab Tests




    Health Plans & Much More

    Available on


    Join 2,00,000+ subscribers who get personalised health tips in their inbox

    Disclaimer : Livlong 365 is not an insurance company. We are a healthcare company who partners directly with health & wellness service providers that guarantee services to our members.