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





First day last mens. 14 Feb 2016…ovulated on the 28feb..had unsafe sex on 27 Feb…28feb and 29 but on the 29 he didn’t ejaculate but I think precum got me…Lol…now today is the 14 March.. was supposed to get period on the 13 March but didn’t…have been extremely tired..cm..moved from thick egg white–dry–clear/watery—white cream like.. nipples are a bit sensitive… have been dizzy here and there..there’s a watery fluid coming from my nose without any effort..tested before period was due but it was negative..really hoping for a positive
Hi, If you have not got your period till not, please take a pregnancy test again. All the best!
Hi ani here!
My last period was on 10 Feb and today I had pain in lower tommy
But today 1 drop is coming like period.
What you suggest to me
I got married in last year past 8 Month it was start in December 17,2015
My 1st miscarriage was in jan
What is the issue
Hi Anni, have you got your period by now?
Hi. My period was on February 24, 2016; my ovulation days are 7-11th of March. I had sex the night of the 12th. Is it possible that I could get pregnant? My cycle is 28 days.
Yes, it is possible that you conceived. Good luck!
I had an abortion 7 weeks ago. The pill one. I was bleeding for approx 7 days. Me and my boyfriend had sex after that and I didn’t want to take any risk so took I took a pill. I did 2 – 3 preg tests and it’s negative. But I still haven’t got my periods. What do I do?
Don’t worry about your delayed period – in most instances, a menstrual cycle is expected within 4 to 8 weeks after an abortion.
Hi. I had my Jan period on the 09th of Jan and Feb period on the 11th Feb. I’m still waiting for my March period. I had unprotected sex on the 29th of February. Can I possibly be pregnant?
My period started on 8th to 11th of march 2016 and then had sex on the same day of 11th. Could I be pregnant?
Yes, it is possible but it depends on the number of days in your cycle. Women with a short cycle, for example 21 days, who bleed for 7 days, can ovulate and get pregnant right after their period.
On the other hand, with a regular 28 to 30 days cycle, ovulation typically occurs on the 13th-16th day so the chances of getting pregnant after a period would be low for these ladies. It really depends on your menstrual cycle.
My fertile week was 25-29th Feb 16 and on Friday I got sent home from work due to having tonsilitis and the anti biotic they gave me made me really sick. Could this be a sign I have conceived? I was due on my period yesterday but no signs of that at all just constantly feeling sick tummy ache and I have refused to take the antibiotics. Is it to early to do a hpt?
I have been highly stressed and depressed so bad lately a couple times I got major headaches. I’ve been thinking about a lot. I lost my virginity to my boyfriend on Feb 23. It was VERY quick, he was supposedly a virgin too. He stopped after 4-5 thrusts to get another condom because I think he produced a lot of fluid. Like an inch high of sperm!! He saw I was crying and stopped and comforted me while tearing up too.
A few days after I felt weird in my lower abdomen and have been gassy a lot lately. My chest feels like it has been getting bigger and today I was supposed to get my period, but maybe it’s a day late like last month!!?! I craved salt heavily 4 days after it happened. I’m not on the pill because I promised myself and my parents I wouldn’t do it. He couldn’t keep his stuff in his pants. I hate sex. I’m only 17 he’s 18. WHAT IS THE POSSIBILITY OF BEING PREGNANT?
The chances of you getting pregnant depend on the number of days in your menstrual cycle and the first day of your last period. Can you confirm this information?
If you were not ovulating when you had sex then the chances of you being pregnant would be low. On the other hand, if you were ovulating or fertile at that time then the chances would be high. Also, if you conceived at that time the symptoms would not be experienced so soon.
My period is due March 16th but my period came 5 days early. My fertile days was Feb 28 – March 4th. I had unprotected sex March 2 and March 4. Could I still become pregnant and miss my April period that’s due on the 13th?
Hi, I haven’t had a period since Jan. 11 (first day of last period). I been to an Ob-Gyn, taken a blood test and 4 home tests, all negative. What should I do?
You now need to have your doctor determine if you have any issues with your hormones. You need to determine why your period is delayed since you’re not pregnant.
No I did not have have that no egg white mucus at all, today I am 7dpo and feel normal from 4-6 dpo I was very tired taking two naps a day and had very watery and sticky discharge. At 5 dpo I had cramps on and off and a sharp pinching pain on my left ovary for about a minute or so. Had a very bad sore throat at 5 and 6 dpo. All my symptoms are gone today . I did a opk test and had a faintish second line. Don’t know if I could be pregnant or what I hope I am !
Carmen, I think you should try taking a pregnancy test to be sure. All the best!
Hi. I am a 22-year-old and I have recently noticed that I skip a month after every period, i.e I had my period on the 18 Nov 2015, missed December then had my next one on 6th Jan 2016, then again missed Feb I started today 12 March again. The dates are also changing a lot I can’t keep up anymore and I don’t even know when to expect my period.
Hi help me out !!! I had a bad period DEC.29 .15 took provera pill for 5 days the bleeding never stopped tho and then after that I had intercourse Jan .15th it shouldn’t of happened but I was irresponsible for messing around like that and tested on Feb.1.2016 negative then got a period the next day Feb.2.16 lasted till the 6th and after that I tested on the 6th and 7th again negative pregnancy tests , so I had sex with my boyfriend from Feb .8.2016 -Feb.23.2016 and never got a period march I tested on the march.8th and got a positive pregnancy test twice my question is it possible to have gotten pregnant Jan 15th or is it more likely that I’m pregnant by my boyfriend who I had sex with after that period on the 2nd we did it from 8th to 23rd ?
Hi Brenda, if you are 100% sure that from Feb 2 to Feb 6, your bleeding was due to period only and not any other kind of bleeding, then the most chances are that the pregnancy is because of intercourse in between 8th to 23rd Feb.
Ann:I’m 36years and for about 2years I have never had my period and always have abdominal pain when I’m due for the period and I am trying for a baby
Hi Ann, I would see a professional for it.
Hi there, just a quick question. I had my last period on the 8th of February and it lasted 5days. In between the period till now I have had unprotected sex . I am yet to get my period for the month of March. Is there a possibility I am pregnant. Today is the 12th and still no sign of my period.
If you had sex during your ovulation period then you’re at risk of becoming pregnant. Continue to monitor your body to see if you conceived.
Hey im have problems. My last period was feb 9,2016 and i was suppose to get my period march 7,2016 and i still have received my period. Me an my boyfriend had iendfeb 19-21 then 23-25. I dont know when i ovulate and as well as I just got off birth controls in 1st of february. Im scared to take a pregnancy test
Hi Maria, I can understand your fear, but there is no better way to make sure you are not pregnant. So please do take a pregnancy test. All the best!