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 was December 31/2015 had sex January 10 keeps getting negative results. I want to have a baby what should I do?
Trying to conceive can be very frustrating but the information provided via our blog will make the process easier…read more here http://womanjunction.com/how-to-get-pregnant-guide/
Hi my last period was on the 22 nd of December 2015 and today is 30 January 2016 have a 25 day cycle and no period her did a test on the 26 January it was negative what to do did I test to early
The first day of my last period was 5the January 2016 .. it ended January 10th … when is my next period…
Your last period was the same as mine January 5th 2016. You would need to know your cycle length to determine when u would get your next period. I have a 26 day cycle and mine was due on the 31st but nothing yet and today is the 2n d of February. Keeping my fingers crossed. *Baby Dust to everyone
Had an medical abortion in october 2015.. then next period cam on dec 6th then My last lmp was on 9th jan 2016 it ends on 13th jan 2016.. i had sex with my partner on 6th, 10th, 12th, 14th 15th, 17, 18th, 19th day from my lmp.. we are expecting baby.. wen i should take pregnancy test… before abortion i had regular 30days periods.. plz confirm…
I had my period on 4th January 2016 and it only last two or three days but today is the 28th and spots are on my panty liner, but the problem is that I don’t know when is my next period coming. Can anyone tell?
If you’re already spotting is could mean that your period is near. We cannot confirm the date of your period without knowing other important information. Was the January period the first time you menstruated?
You probably are pregnant I had the same thing with my daughter good luck!:)
Hi, I am pregnant but I’m having trouble understanding when I conceived. I had sex July 30, 2015 in the wee hours but started my period later that same morning. I have a 28 cycle, bleed for 7 days. I had sex again on August 9, 2015. Please inform me about what I need to know to help me understand. Thanks.
Based on your 28 days cycle and the date of your last period, you were most fertile from August 11 to 15, 2015. So you conceived during that week; it is highly likely that August 13 was the actual date of conception. 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.
Me and my bf got sex on 18 of december 2015. After the sex I got my monthly period. Then 20, 22 and 24 december 2015 we sex again. I take amoxiciline capsule last december 2015 4 times, at the same time I take my pills regularly. Then 18 of january 2016 my period came but 2 days long only usually it takes 5 -7 days before monthly period gone but also I got my bleedbing very ligth. Its possible I’ll be pregnant?
Hi, i got my last period on dec 25 and last till dec 31,2015.. I didn’t take my pills which is diane, now i had sex on jan12 2016, the next day i took diane till today jan 27,2016.. I still have 6 pcs of pills to be finished, is that safe? Will i get my period after the pills?
Hello, In order for your birth control to work you have to take them properly because if you miss your pills and have unprotected sex you can get pregnant,it will only not be safe if you are pregnant and take them without knowing.
Hi I had my periods on 1st January till 5th January. My question is until now I haven’t got my periods yet!!
Hi. I have a question. I had my period December 25-28th it was not as heavy as usual & that’s odd. It was also odd for me to have a period on those days. Typically my period falls on the 4-7th of the month. On January 4th I spotted just a little tiny bit and that was it. I haven’t been feeling right. I’ve had unprotected sex. My period tracker said I should have started on the 25th on this month seeing as how I had a “period” on December 25th. I’ve been really crampy and my stomach is gurgly. Could I be pregnant?
Hi,you could be pregnant its possible since you did have unprotected sex the only thing you can do now is take a pregnancy test.
I was supposed to come on January the 11th. My las start date was Dec 12 and nothing since then. I’ know sometime my body can be very funny action . I’m expericing menstral like symptoms with like nausea.. Any ideas on what I should do next? I haven’t take a test yet I said I would give it to this weekend just to make sure…
Hi, Yeah i suggest you wait then take a pregnancy test that’s the only thing you can do now until you find out if you are pregnant or not.
My last period was on the 8th of jan. 2016. I want to get pregnant, how can I
hi, please read this post: http://womanjunction.com/how-to-get-pregnant-guide/
good luck!
Hi All,
I had my last period on the 13th December and think I was fertile the last week of December until 4th Jan, I was expecting my next period atleast on the 17th of Jan, but nothing yet I have taken a pregnancy test day before yesterday it was negative. I only feel cramps like my period is coming but none since yesterday. am I pregnant? or still a late period? my longest cycle was 37 days now I am on 45 days. please any suggestion will be appreciated.
I skipped the month of December. I waited and waited and nothing. When my period decides to finally come which was January 9th I was on day 44. I just had a very late period. Wait a couple of more days (3) and if you don’t get it I’d take another pregnancy test or go see a doctor.
A late period sometimes is a early miscarriage I had one and if I never took a test I would have never known, it happens to the higher percentage of pregnant women and they never know.
Hi my last period was on December 18 2015 or December 21 2015 and I had unprotected sex on January 6 2016 and I was supposed to get my period either by the 14 or 18 and my menstrual cycle is “28” days. I haven’t gotten my period yet, can I be pregnant?
Hi. My last period started on Jan 11th I have a 28-day cycle and my fertile window was the 16-22 I had sex on the 14th and 21st. I know it’s still really early but I have been experiencing fatigue bloating frequent urination and the top of my abdomen is tender and sore. Is it possible that I am pregnant?
Once you have sex during your fertile days then it is possible to become pregnant. It’s best to wait a bit to see if you’ll miss a period. You can get the most accurate pregnancy test 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.
Ok, Nov.11,I had a miscarriage. True to the date my doctor gave me, I had my period the next month Dec. 11. It is now Jan, 25, no period. Could we be pregnant?????