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





My period started April 3rd I ended on April 10th and had sex on April 11th can I be pregnant? If so when should I take a test I have irregular periods so there hard to track I’m very lost need help.
Hi, last month my last day of my period was on the 20 and had sex onthe 3rd of april, in april my period came onthe 4th, which was 6 days early. On that day i was cramping and had light blood the next had clits coming out once, went to the gp for sonar there was nothing wrong. Am i pregnant? Im on wafferin.
Hi Grace, sonar can fail to detect pregnancy if it’s too early. Please wait until 5 weeks after sex, (1st May) to get the correct result. You can also take a pregnancy test. All the best!
The first day of my last period was on March 7, 2016. I made love last April 2-3 and again on April 10. I still don’t have my period until now 🙁 is it possible to be pregnant now?
Hello, my last period was on March 17th 2016. I thought I should have my period by now but I haven’t. I had sex on 3/25/16 and 4/2/16 and the condom broke. Should I take a test now or should I wait it out? My cycle is always on time. It’s normally a 26-28 day cycle.
It is possible to become pregnant at that time. Take a test within 3 more days to confirm if you are.
Hello! My last period was on April 10 and I had sex with my hubby on that day. Can I be pregnant? Thanks.
The chances of getting pregnant on that day would be low if you have a regular 28 days period. Women with regular periods, ovulation typically occurs on the 13th – 16th day.
I took pills in 3 years and stop taking last march 9. My first day of period is march 13. I have a sexual intercourse last april 5 using pull out method. Do ihavea chance to get pregnant?
Hi Ely, yes there is a chance. Pull out methods are not safe. So if you are not trying, please use a protection.
Ok thanks, can you please please tell me when is the best date to take a pregnancy test…. I’m very thankful if you’ll response again.
please check this post: http://womanjunction.com/home-pregnancy-test/
Hello my last period was March 15 to 20 an i had sex on the 2 of April is it possible that I might get pregnant
Yes there is a good possibility.
Hello I had my last period on the 15 to 20th of March. I had sex on the 2nd of April and I have done 3 pregnancy tests; they’re all negative but my period doesn’t come as yet. Is it possible that I’m pregnant or not?
Hi, my last period was on March 7, 2016 and had sex on March 20 to 25. Until now I don’t have my period yet, can I be pregnant? When should I try a pregnancy test? Please help me. Thanks.
If you have a regular 28 days cycle then it is possible that you were fertile at that time. You can get the most accurate result if you wait at least one week after missing your period to take the pregnancy test.
i took a test this 14 of April and yes I’m pregnant!???? I consulted an OB but she suggest to delay my ultrasound and rescheduled it in may 5.. I think I’m 5 weeks day 7 now.. tnx & best of luck ladies! ????????
congrats! 🙂
Yes u can be pregnant I had my period march 8-12 took test first week April I am pregnant but doctors says they see a sac and no baby
Yes you can be pregnant. I had my period on March 8-12. I took a test the first week April. I am pregnant but doctors say they see a sac and no baby.
If I started my period April 1st (I have a 22 day cycle) lasts about 2-3 days. I had sex with my husband on the 3rd and according to my research I ovulated the 8th could I be pregnant?
Yes Steph, there is a chance of pregnancy. ATB!
My last period was on the 19th of March. My husband and I are trying for baby no.2 I am using the clearblue ovulation sticks but as of yet I still have not ovulated. I was on the pill for about 10 months came of it at the beginning of December had my first period in Feb and again in March. I just don’t understand why I have not ovulated yet.
Hello, Clear blue is a good brand but still you can try using another brand, just in case. Also, when do you test it? If you do it in morning, try doing the test in nighttime. Sometimes that may get a positive. All the best!
Hi, the 1st day of my last period was March 7, 2016 and I had sex on March 10. Can I be pregnant? I still don’t have my period until now.
You may not be pregnant since you were not ovulating at that time.
Hi. My last period was between 29 March, 2016 and 3rd April, 2016. I had sex on April 6, 8 and 9th April. I started spotting on 10th and 12th April, my fertile days. What could be the problems or cause of the spotting on fertile days? Thank you.
Hi! My last date was 13 march 2016 so I had unsafe sex on 18,19,20,21,22,23,and 28, my circle is for 28-29 days. I tested negative and I was waiting period on the 10 April 2016. I missed it. My question is, am I pregnant, what am I supposed to do?
Hi Onica, if you have not got your period by now, please take a test.
Also, if you are not trying, always use protection. All the best!
Me and my partner had sex March 29 and April 2 2016. And I got my period on April 4 2016 then April 10 2016, we having sex again. Do you think I got pregnant? and I have still a little blood comes out.
Hi Margie, if you had unprotected sex on 10th April, then yes there is a possibility. About the little blood, is it bleeding or only spotting? If it’s bleeding then please contact your doctor.
i had my period on 9th of march 2016 and i had protected sex on 21 of march 2016 and the 9th of april have reached and i saw nothing.am i pregnant?
Hi Raina, if it was protected sex, then most likely you’re not pregnant. Please wait a few more days.
I had my period March 18 ,my period was off by the 24th .I’m suppose to get my period on the 16 of April,I threw up yesterday morning,and feeling nauseous from to time..what do u think is going on here and I have a 28 days.between cycles
Hi Arlene, it’s too soon to say anything. If you have not got your period till now, 17th April, then please take a pregnancy test. ATB!