You want to know the dates of your next period, ovulation or due date? You came to the right place. If you’re in a hurry you can go straight to our menstrual cycle calculator (click here) or Infographic with key information about calculating your period (click here).
Check the full table of content below.
Table of Contents
- Introduction
- Period & Ovulation Calculator
- How Do Menstrual Cycle Calculators Work?
- Using a Period Calculator
- How To Calculate Your Next Period & Ovulation Infographic
- Understanding the Menstrual Cycle Properly
- Understanding Your Next Menstrual Cycle and Fertilization.
- Some Important Information Regarding the Calculator
- Learn more
- Frequently Asked Questions
Introduction
If you want to stand the best chance of getting pregnant, then you need to know when you are ovulating. This is the time of the month when women are in their most fertile period. Ovulation usually happens around day 14 of the cycle [1]), while there is a greater chance of a sperm reaching the egg and fertilizing it.
However, one of the biggest problems and question that people have is knowing how to calculate their next ovulation date and when is the best time to aim for intercourse. This is where technology can come in handy. You can use an ovulation calculator, like the one below, to get a rough estimate of when you are going to ovulate next.
Ovulation & Period Calculator
Use this period calculator to calculate your next period (menstruation), fertile period, ovulation, and due date. To give you an estimate as to when those time frames are, please provide the requested information and press the Calculate button (results will be shown below, together with a fertility calendar):
When did your last period start?
How many days did it last?
How long is your cycle?
Below are the results based on the information you provided:
Your next menstrual period is expected to start on
Your next most fertile period is from to
If you conceive within this timeframe, your estimated due date will be
- Pre-Period
- Period Days
- Post-Period
- Peak Ovulation
Please note that this is only an estimation of your menstrual cycle
A period calculator is not the same as talking to a healthcare professional, so this is just to aid you in coming up with the most accurate calculation possible, on your own.
Also, keep in mind that these calculators will be useful to women with a fairly regular menstrual cycle. For women with irregular menstrual cycle tracking other ovulation symptoms or using an ovulation predictor kit might give more accurate results, all of which we’ll cover later one.
How Do Menstrual Cycle Calculators Work?
Menstrual Cycle Calculators vary in complexity. Some will ask you for information such as your average body temperature, as well as various other bits and pieces about what your body is currently going through.
While there are women who measure their basal body temperature, it’s not something that the everyday woman uses.
However, it is a rather accurate way (when done 100% correctly) to determine when a woman is ovulating.
Some feel that these types of cycle calculators are “overkill”, but for those who are using the basal body temperature to prevent and plan a pregnancy, they have this information handy.
If you aren’t into this type of strict monitoring, a simple calculator like the one provided here can give you really good results and help you plan.
Using a Period Calculator
The first thing that the period calculator will ask you is the date of your last period. With so many apps available now, this should be information that is readily available.
And just remember, when calculating your period, you use the first day of your last period. This was the beginning of your cycle.
If you don’t know the exact first day, calculate back from the last day however long it lasted, and start tracking now. Especially if you are trying to get pregnant.
Some will use a menstruation calculator to figure out when to expect their periods and when to expect PMS. PMS is due to the change in hormones that cause periods and pregnancy.
When you are pregnant or during your period, these emotional and physical symptoms subside [2]. Some women can then plan to change their diet a few days before they expect PMS and help to alleviate some of the symptoms.
The next piece of information that you will be asked for is the average length of time between your periods. This is the length of the menstrual cycle. Of course, the human body does vary wildly here, and whilst some months there could be 30 days between your period, others it could be as low as 25.
However, you are only after an average here. Being as accurate as possible is important as this will affect the results that you are given which can have a profound effect on when the calculator tells you is the ideal time to try for a child.
Finally, you will be given your results. Based on the information you provided, it will calculate when your next period is anticipated and also your fertile period which is when you stand the best chance to get pregnant.
How To Calculate Your Next Period & Ovulation Infographic
Understanding the Menstrual Cycle Properly
While you may already have a fair understanding of your own menstrual cycle, there are women who have cycle lengths that vary. Sometimes, your own cycle can be as short as 23 days on cycle and 28 or 30 days the next.
When a variation in menstrual cycle length occurs, it usually happens before you ovulate. This is referred to as the follicular phase which encompasses menstruation as well and ends when you ovulate [3]. A woman generally ovulates between days 12-16 of their cycle which is the start of the luteal phase [4].
There is a multitude of reasons as to why your period could be altered, be it stress or medications, even weight gain/loss or travel. Unless you think you are pregnant, it could be a myriad of reasons that have your period coming irregularly.
Understanding Your Next Menstrual Cycle and Fertilization
If you are trying to get pregnant you need to understand how the menstrual cycle works. The process starts when the thick lining of your womb starts to break up due to the decrease in estrogen and progesterone levels.
Without a sufficient amount of these hormones, your body will shed the lining and it will start to prepare for your next menstrual cycle.
However, if a sperm does make contact with and fertilizes the egg, it will close all pores to prevent more sperms from getting in there. The fertilized egg will stay in the fallopian tube for 3-4 days and then move to the uterus and attach to its wall, staying there for the long haul of pregnancy.
Your body will produce human Chorionic Gonadotrophin (hCG) or pregnancy hormone right away (which can be seen within 6-8 days by a blood test and can take about 2 weeks if not longer to be seen in urine tests) [5].
The body will continue to produce the required estrogen and progesterone hormones so that the womb lining will not be shed and the placenta can grow mature enough that it can support the pregnancy.
Some Important Information Regarding the Calculator
The period calculator above also comes with a fertility calendar. You can navigate through different months by clicking on the NEXT 2 MONTHS and PREVIOUS 2 MONTHS links. This allows you to plan and prepare for your fertile and menstrual periods in the upcoming months.
What you do need to remember though is that the information isn’t 100% accurate as it is impossible to predict the human body.
Your fertile period gives you a good range in when to have intercourse to potentially get pregnant. You can learn more about the likelihood of conception in this article.
That being said, the menstrual calculator is still an extremely useful tool. It provides a simple way of knowing when to anticipate your next period and when is the best time to try for getting pregnant.
This could be a huge help for those with busy schedules to plan their days to start their family.
Learn more
Want to learn more about your menstrual cycle? Find out how does the Fertility Calculator work or how to to calculate your period manually.
Want to know if you’re pregnant? Take this online pregnancy test, read more about the most common reasons why your period might be late or find out when it’s the best time to take a home pregnancy test.
FAQs
How do I calculate the length of my cycle?
Can I have sex during my period?
What is the average length for periods?
My period is really heavy; what can I do to change that?
Can I get pregnant if my periods are irregular?
How do I know if I need to see a doctor because my heavy periods?
Can I prevent PMS?
Do you have any other question about your period, ovulation, pregnancy or other related topics? Check out our Frequently Asked Questions page.
References
- Your Fertility. Women’s Guide to Getting the Timing Right [link]
- Mayo Clinic. Premenstrual Syndrome (PMS). [link]
- Better Health Channel. Menstrual Cycle. [link]
- see above #3
- WebMD. Pregnancy and Conception. [link]
- Eleanor Jones via Cosmopolitan. 10 Questions Period All Guys Want Answered [link]
- Playtex. Period 101. [link]
- The University of Iowa. Birth Control Pill Fact Sheet. [link]
- WebMD. Slideshow: Answers to Your Top period Questions. [link]
- see above #9





Hi, I had my periods on 22nd April, up to now I haven’t seen them, I had no sex during those days, what could be my next period date.
Hello Vio k, use the below link to find out:
https://womanjunction.com/
I had my period on 4th April and I was supposed to have it on 2 may but my period isn’t in I haven’t had sex for a year and months now so please what’s the problem
Hi there Magdalene, your period might be irregular for several reasons. Click here to find out.
i saw my period on the 23 April 2019 and when is the next one
Hi there click here to find out when your next period should start.
I had my period on 30 March then had sex on 3rd April and my boyfriend released inside but I took morning after to my surprise I had my period in the same month on 10april. I had sex again on 3rd May and fourth May that was on Thursday and Friday but I took the morning after on Saturday. I know this month isn’t over yet but I’m very worried today is 21 may I did a pregnancy test a week ago it came back negative .
Hello Tisa, the test was negative, therefore you are not pregnant.
I was supposed to get my periods on 31st April but I didn’t get it and I had sex with my boyfriend on 6th May and until now I’m not having my periods. Is there is a possibility of getting pregnant ??
Please help me out I’m really scared
Hi Riya, Since we don’t know when your last period was, I wouldn’t be able to give you a straight answer. Your best bet would be to take a pregnancy test. Other than that consider that your period could be late due to medications, stress, weight changes, travel, or illness as well.
I have menstruation last march 27 and ends on March 31, but i have sex wth my boyfriend last april 7 without a condom. And i’m so stressed after that day happened to us, and until now im waiting but not yet. Its may 13 but i tried pregnancy test but its negative, im so stressed about this issues.
Hi Angel, April 7th would have been at the beginning of your ovulation period, so it’s quite possible that you are pregnant. IN the future you can always consider emergency birth control within 72 hours to prevent pregnancy. However, with that being said you should take another pregnancy test. If negative and you still haven’t gotten your period within a week or so I would make an appointment with your doctor. They can do a blood test or determine if everything else is okay as well.
My last period 25 April. l had unprotected sex last 2 or 3 days. l have nausea. am pregnant or not
Hi Simi, I don’t know if you are referring to the beginning or the end of your period being the 25th of April. Regardless you wound’t be in the fertility window. Nausea also wouldn’t show up this quickly so that’s likely unrelated.
Hi, please I saw my period on 16 may, when next will I be expecting it again?
Hi Precious, we haven’t hit the 16th of May yet so I am a bit confused.
I started periods on 3rd April and expecting to be on period on 1 May but till today there is nothing. I never had unprotected sex, I can feel the signs of periods but there is no drop
Hi Susi, if your period isn’t regular yet (I don’t know your age) but it could be that your cycle has not fully found it’s cycle yet. However, anything could be the reason from stress, weight loss/gain, illness, medications, etc. If you have’t had sex then you aren’t worried about pregnancy.
hiya I had my last period on the 3rd April and now it is the 5TH of May what are the possible reasons that I may not have strated as I am always on time for my periods and have never been late ?
Hi Ikra, could be a few reasons, pregnancy, illness, medications, travel, etc. The body will change and possibly delay your period if there is a lot going on. If it’s possible that it could be pregnancy I would recommend a pregnancy test.
My girlfriend had her last period beginning on 10th April, we later had unprotected sex on 27th April.could she get pregnant?
Hi Mark, while based on a 28 day cycle her fertile period was between April 20th through the 24th, it could be earlier or later. And if she hasn’t gotten her period as of this response it’s a large possibility. If she still hasn’t seen her period, get a pregnancy test.
hiya there. I started my last period on the 3 April 2019 and now it’s the 5th of May and my period has not still come. Is there any chance I could be pregnant?
Hi Kirsty, it’s quite possible as you would at this point be two days late based on a 28 day cycle, however multiple things could be the reasons for. delayed period such as illness, medication change, weight changes, etc. However, I would recommend taking a pregnancy test.
Hi, my last period was march 29th and I had unprotected sex April 10th and April 13th and still haven’t gotten my period. What does this mean?
Hi Jessica, you should be taking a pregnancy test at this point to determine if you are pregnant or not. You are nearly a week past your anticipated period so I would do that first in order to determine what it means.
I started my period on the 22nd of April and I had an unprotected sex last day of my period and now have started another period on 2nd of May.is it okay??
Hi Funmi, I would say that what you are experiencing right now is not a period possible ovulation bleeding. Based on a 28 day cycle you would be ovulating between the 2nd and the 6th of May so this is most likely what you are currently dealing with instead of an actual period.
My girlfriend started her period on 22nd April and I expect to have unprotected sex on 9th may, will she get pregnant?
Hi Mugadu, While it’s not during her ovulation period according to a 28 day cycle, anything is possible. She could ovulate sooner or later. If you aren’t looking to start a family with her at this current time I would recommend protection. While there are women who are extremely regular, not all women are. There are plenty of option available to you both for preventing pregnancy, I would look into them.
Please what can cause irregular periods. Before I used to have my period for 5 days and now since January it is 3 days.
Hi Ademide, there are a lot of reasons that you could be experiencing a change in period. Now if you are just starting out with your period it could still be working into it’s regular pattern. Also consider if you have had stress in your life, change in medications (especially new birth control), traveling, medications, illness, drastic weight changes, etc. Keep track of it and see where it goes. If any of these things sound like you then just know that it could change back to your 5 days, however this could be your new normal.