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





Okay the first day of my last period was March 31st. I should have got it again April 30th or May 1st. Nothing yet. I have very sore boobs, headaches, some cramps that come and go, and I’m more tired. I took a test yesterday and this morning and they both came out negative. Is it to early to take one or am I just not pregnant and I’m gonna be late ?
It could be that you’re not pregnant. If your period is eleven days late and you tested negative, it is highly likely that you did not conceive.
Hi, my last period was on 20th March and I had intercourse on 13th to 15th April after that and my periods have not come yet, is there any chance specific of me being pregnant?
Hello Remya,Please take a pregnancy test to check if you are pregnant or not. For accurate results, Pregnancy test is taken 10 days after missed period date. Since you might have had that much gap, please take it and get assured.
I had my last period yesterday and according to my own calculations,,my next period was found to be on the 3rd of June just like u guys calculated,,I just wanna say thanx for informing me about my most fertile time frame n this r the dates um gonna try to concieve,,thnk u very much
Your welcome Judith. You could return to us anytime you want answers for any further questions.
The firstday of my last period was March31 to April 5..we have sex intercourse with my hubby April 22-23.theres. possible to got pregnant? Even though he had widrawal?
Hi Rhen,
Yes, it’s possible. Even if one sperm gets in contact with vagina, then there are chances of pregnancy. Please refrain from using withdrawal as a means of protection. Use protection until you want to try for pregnancy.
Comment Please. I had my last menstrual flow between 21-24 march 2016. I started the current one on 5th may 2016, What could be the problem please suggest?
Hello Larry, Late period could be be because of a lot of reasons like illness, stress, weight, change in schedule, medication, hormonal imbalance etc. Sometimes it could be just temporary so do not worry, track your periods well and if you face continuous irregular periods, go consult a doctor.
Hi, I had my baby on March 11 2016 and still not have started my period. I bled for almost 3 weeks postpartum. Just wondering when my period will return. Thank you.
Hi Melyn, It’s hard to say exactly when your periods will start again. The timing is different for every mother, and it depends on your body, as well as how you are feeding your baby. If you’re breastfeeding day and night, it can be up to a year before you have a period.
The same applies if you’re supplementing with formula. In other words, the more often your baby breastfeeds, and the more time she spends at your breast, the longer it may be before you get your periods again.
My last menstrual date was April 6-10.And then I had sex on 11th.Now my next menstrual should be around may 4 .Unfortunately I missed it and now I’m delayed for 2 days? Is it possible that I’m pregnant?
Hello Ane, The day just after your period is not considered a fertile day, i.e. chances of getting pregnant just after your period is a little less. It is too early to decide that you could be pregnant. Please take a pregnancy test after 10 days of your missed period date to check if you could be pregnant. That is considered an accurate test method.
Hi, my period started on 26th of March 2016 and ended on 30th of April , when are my suppose to be fertile. Please advice me.
Hey Loise, If your cycles are regular, it would be on Day 19-21, so 14th to 16th May would be your fertile dates with 15th being the ovulation day.
Hello. I have a 23 days cycle, 05/05/16 was the first day of my period. I am trying to get pregnant for about 6 months and being married for 1 year. I know it is not easy but, I am hoping for accurate answers as possible. Thanks in advance for all of your help.
I know how frustrating trying to conceive can become. You have to ensure that you have sex when you’re ovulating to increase your chances. Click this link to access our article on how to get pregnant http://womanjunction.com/how-to-get-pregnant-guide/ Good luck.
Hello all! I had my last period on March 11-14 of this year. My hubby and I started trying on the first week of April but have had bfn on all pregnancy tests. Just took one this morning and still negative. Slight cramping here and there, no nausea since a couple of weeks ago. Breasts are extremely sensitive (have been for two weeks) but still no sign of Aunt Flo. Should I go ahead and go to the doctor? What would y’all do.
Hello Ashley, Sexually active women may miss their periods because of reasons other than pregnancy, they could be hormonal or just anxiety or worrying. Since you have taken a test and it is negative, there are chances that you are not pregnant yet. For a peace of mind you could go consult a doctor and be assured.
My last period was April 19, 2016. My next period shouldn’t be until May 17, 2016 according to the menstrual calculator.What are the chances of me getting pregnant if I had unprotected sex a day after my period. Now my nipples are sore to touch, mouth dry and I’ve been feeling bloated.?
Hello Amazing, The day just after your period is not considered a fertile day so your chances of being pregnant are less. The symptoms you are experiencing could also be symptoms of PMS or just anxiety. Please take a pregnancy test to see if you are pregnant or not.
Hi, my last period was on 18 December and the next day me and my partner had unprotected sex. Am I pregnant?
the first day of my period was on the 24th, when will i likely be ovulating
I had something like sex on 5th April 2016, I saw my period on 6th April 2016. My cycle is 28 days and I have not seen my period. Can I be pregnant??
You may not be pregnant since you were fertile from April 18 to 22, 2016.
Hi,
My last period started on 3rd April. My average length of cycle is 30 days. We had unprotected sex on 19th April (which is my most fertile days, in fact my ovulation date as per the online calculator). I haven’t got my periods yet, which was due yesterday. My cycles are very very regular. Spot on. I am urinating too frequently, I have, acne on face, I am eating a lot. No other symptoms of pregnancy though. I took a home pregnancy test and it was negative. Can i be pregnant ?
Hello Priya, The symptoms that you have pointed out are pregnancy symptoms but also they do not clearly indicate pregnancy. There could be other reasons for it. For accurate results of pregnancy test you should take it after 10 days of missing your expected period date.
I have not yet seen my period again and the last time i have it was on March 16.. What should I do or the possible reasons? My menstrual cycle is irregular.
You can now take a pregnancy test to confirm if you’re pregnant. If it is negative you need to see your doctor to determine what is causing the delay in your period.