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





Good day I saw my period on the 5th of September and we are in 5th October I don’t know if I am pregnant or not
I had my last period from 27 Aug – 1 Sep, and I expected it on the 27 nd 28 of Sep but it never showed up till on the 3rd Oct. Pls what much have caused the delay and when is my next period?
Hello. Your period may be delayed for many reasons including those discussed in this article http://womanjunction.com/missed-menstrual-cycle/ The number of days in your menstrual cycle will help to determine the date of your next period.
Hello, I’m Kitty. Well I was or still am pregnant I was 16 weeks about to be 17 weeks. I started bleeding lots blood clots went hospital 1-2 days after all they did was a pee test said I’m not pregnant then sent me to a doctor who does stuff for this kind all they did was pee test but didn’t run it or anything they haven’t even called me. Thing is I still feel like I am mentally – I had every single symptom .-. I’m supposed to be on my period but nothing, no period symptoms though. Please respond with your opinions
It is likely that you’re having a psuedo pregnancy where you had all the symptoms but you were not actually pregnant. You need to consult further with your doctor to diagnose the problem that you’re having
I saw my period on the 28th of August and it end on the 2nd of September. On that September, I do not see it at all but it came out on the 2nd of October. I want to know when my period stops, how many days will I count out in order to meet my husband for me to get pregnant. I was pregnant before but the baby died inside of me. Please I need your help, I am a married woman.
Typically, the menstrual cycle will last for 28 days, which is calculated from day one of a menstrual period to day one of the next cycle. Ovulation typically occurs 14 days before the start of your menstrual period. If your cycle lasts for 28 days, you can ovulate on the 14th day like the average female. However, you will start ovulating around the 11th day if you have periods 25 days apart. Alternatively, you will not ovulate until the 20th day if your cycles are longer, like for 34 days. If periods are irregular it would be more challenging to determine the fertile days. You should also read this link for more information http://womanjunction.com/fertile/
Hi, I had my last period august 31st 2015 it lasted 4 days now its October 3rd. Could I be pregnant? If so is it too early to take a home pregnancy test? When am I able to take one?
The best time to take a pregnancy test is at least 1 week after you’ve missed a period. Your last period was 2 months ago so you can take a test now.
My bf and I are ttc, my lmp was Sept 19, we had sex sept 26, 29, 30, oct 1, & 2, what are our chances of concieving? My fertile window is oct 1-6 so we will continue to try every day until the 7th. This is our 2nd month trying.
My last period is 16th of Sept 2015. I had sex last 22 and 23rd of the month of Sept. Is it possible that I’m pregnant?
Your chances of being pregnant depends on the number of days in your menstrual. This information needs to be confirmed.
Hi y’all !
My period has just returned after 3 months of giving birth ( September 6 , 2015 ) while breastfeeding .So based on my calculation says my fertile days are from sept 15-20.so we had sex 15,18,19 with unprotected sex.we didn’t have sex on ovulation day which was the 20th.And after that 25th day came I noticed a raw egg discharged I was so wet I didn’t really got bothered then we had unprotected sex again on 27th.my questions are could I get pregnant again while breastfeeding ? And what was the raw egg meant they say its the time you ovulate? How come I ovulate if I already did ? And seriously I didn’t have raw egg discharge when the time I expect I ovulated. pls help I’m confused ????????
Healthy Baby Elise was born may 28 ( 40 weeks and 2 days ) ❤❤❤
Hi Elie, Yes. In general, you’re less fertile, but not infertile, while breastfeeding. Although you may not menstruate for months after giving birth, your body usually releases its first postpartum egg before you get your first period. So you won’t know you’ve ovulated until two weeks later — when you menstruate. Egg white discharge usually means you are ovulating.
Thank you! Should I need to take a home test?
And what are the chances for us to get pregnant since we’re trying to get pregnant again but we’re not really so trying hard.
Hi. So I had my last period on August 24 and ended on August 29. Nothing happen in September and it’s Oct 2. How much longer should I wait to take a pregnancy test?
You can get the most accurate result if you wait at least one week after missing your period. In addition, the result might be even more accurate if the test is done first in the morning as the urine is far more concentrated at this time.
Im in the same situation and I’m nervous
You should take a pregnancy test right away. You are overdue to get your next period
Hi. I was supposed to have my period on the 30 of June 2015 but I missed it, then I took a pregnancy test on the 15 July it was positive. So today is the 2 october 2015 I need to know how many weeks or months am I?
What was the date of your May period? This is needed to give you the most accurate information.
I had my period twice for month August-September. And my last period started on 3rd Sept. I did try to conceive on the 21st September and still haven’t have my period until now. Or my period hasn’t due yet? Or could I be pregnant?
Hi Alison, Once you had unprotected sex its always possible to become pregnant but you wont know for sure until you take a test or miss a period or 2.
I was already 4days delayed when we had sex and until today I haven’t have my period. Why is it like this?
If you missed a period and you are not pregnant, you might want to know why this happened. Some of the causes of a missed menstrual cycle include: stress, change in regular schedule, travel, illness and use of certain medications. It would be best to consult your doctor for help in identifying which factor is causing the delay.
If you think you may be pregnant – take a test at least 1 week after a missed period for more accurate results.
Hi I’m 4days delayed when we had sex, until now I didn’t have my period yet. Possible that I’m pregnant?
Hi. I was supposed to have my period on the 21st of September but it didn’t come. My husband and I had sex on the 24th. And until now I still haven’t had my period. Is there a possibility that I’m pregnant or not? Thanks.
Hello. You can take a pregnancy test at least 1 week after you’ve missed a period to get the most accurate result. So wait a few more days before you take the test.
Hello. My last period was Aug 29 2015. I took a home pregnancy test today Oct 1 2015 but it was negative. How long should I wait to take another one?
Hi. You can get the most accurate result if you wait at least one week after missing your period. In addition, the result might be even more accurate if the test is done first in the morning as the urine is far more concentrated at this time. The urine-based home pregnancy tests offer great accuracy. This accuracy will depend on several factors such as how early the test is taken, if the instructions were followed closely, when ovulation occurred in the cycle as well as how early implantation takes place, and the sensitivity of the test.
Hello. My last period was Aug. 29, 2015. I am having some symptoms of pregnancy. I did take a home pregnancy test today Oct. 1 2015 but it was negative. How much longer should I wait to take another one? And is it possible I could be pregnant with a negative test?
Hello. Please refer to section 5 (Pregnancy Tests) of our FAQ link at http://womanjunction.com/faq-frequently-asked-questions-menstrual-cycle-pregnancy-ovulation-abortion/ it will provide answers to your questions