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
I had my period on 4th of Nov, and I had unprotected sex from on d 8th 10th,11th 12th 13th 14th, it’s possible I get pregnant during those time of sex?
Your chances of being pregnant depend on whether you were fertile on or around the dates that you had sex. Can you confirm the number of days in your menstrual cycle? This information is needed to provide you with the most accurate response.
I had my menstrual on the 29 of October and it ended on the 3
02 of November. On the 14 of November i had unprotected sex with my husband. Can i be pregnant?
I would need to know the amount of days in your cycle to be able to guide you better.
My flow always comes on 3rd of every month..but I don’t know how to calculate my cycle.
The menstrual cycle starts on day one of the bleeding to day one of the next. On average, the cycle lasts for 28 days, but it’s normal to have it longer or shorter. So if one period started on July 10 and the next one started on August 5, then you that person would have a 26 days. This is so because there are 26 days between the first and second period. Your period comes on the 3rd of each month so count the number of days beween those dates. You would get 30 to 31 days. This means that you have a 30 to 31 days cycle. Read this article http://womanjunction.com/menstrual-cycle-calculating-manually/ for more information.
I had my period July 5th and it ended July 10th I had unprotected sex July 21,22,or 23 my next period was due August 1st which came and was over august 6th but it started off brown which never happen before. Then I had sex with someone else on the 15th of august and now I’m 14 weeks and some days pregnant. When did I get pregnant and by who? I’m disappointed in myself and need some type of knowing.
In July, you ovulated from the 16th to the 20th. In August, you ovulated from the 12th to the 16th. Since were 14 weeks plus on November 13, and you had a period on August 1, then it seems you were impregnated in August. Did you do an ultrasound to confirm how far along you are? The ultrasound will give you a good idea of the foetus’ development and age. In this instance, the age of the foetus should be able to help to determine when you conceived. In other case only DNA can confirm paternity.
I had my period on 2 Oct to 6 Oct my cycle is 28 days. I had it again on 18 Oct pls when will I be fertile?
You would be fertile from October 30 to November 03, 2015. Your next menstrual period is expected on November 15, 2015.
Hi Ladies. I am hoping someone can help me. My husband and I have been trying to get pregnant for the last four months now without any luck. My period was due yesterday (i have a 23 day cycle) and it was a no show. I did a home pregnancy test this morning but it was negative. 🙁
What I am unsure of is did I perhaps test to early? Since my cycle is shorter perhaps the HCG levels are still very low?
Also, I saw my gyne last month who put me on medication to make my flow a bit lighter as I bleed very heavily and every three weeks. Can this affect the regularity of my cycle?
And my third problem is that I am taking lithium for my bipolar disorder. How greatly can this medication affect my chances of getting pregnant?
The best time to test is to 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.
With respect to your second question, it depends on the type of medication that was prescribed.
The lithium may not affect your ability conceive but it “has been linked to certain birth defects and should be used with caution in pregnant women, especially during the first three months of pregnancy.”
My last period was 8th Nov to 11th of Nov. So when will it be my fertile period because I want to get pregnant.
Your fertile period can be determined only if the number of days in your menstrual cycle is known. Please provide this information so that an accurate response can be provided.
I had my period on 23of Oct to 27 during my last period I was having bad discharged odour for like 3days, not until I used warm water and dettol with ampiclox, and am still having another period 2day which is 15 of Nov. B4 I started another period 2day I was having Sex pain and vagina itching,pinning and went 2 doctor 4 complain and he gave one tablet 2 be inserting in 2 my vagina yesterday. So I now saw my period 2day, seriously need a baby. Pls I need ur reply very fast
Hello, I am 25 yrs old I usually see my period every 25 days for instance if I see it on the first (1) my next seeing will be on the twenty fifth (25). When is my menstrual cycle, length and when i’m I supposed to ovulate in between this day?
Note that some of the terms mean the same thing and are used interchangeably. The menstrual cycle is the same as the lengths of days in a cycle. In your case, you have a 25 days menstrual cycle which is the same as saying the length of your cycle is 25 days. 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 since you have periods 25 days apart.
Hi, I had my period on 9th Oct that lasted 5 days and had sex the next day unprotected sex and took Postinor2 the next day and had a light bleeding on 21-22 Oct. My period is due to come on 7 Nov but have not seen it and I had sex unprotected on 11 Nov which I took Andrew’s liver salt 2 hours later. I’m confused cause am having menstruation signs but have not seen it.
Hello. Have you now seen your period? A side effect of Postinor 2 is that it will delay a woman’s period. If after using Postinor 2 you have unprotected sex again, then you’re at risk at becoming pregnant. Andrew’s Liver salt is for indigestion, it does not have the same effect as Postinor 2; it will not prevent conception.
I started my period on 26th of Oct. And I finished on 28th of Oct, my period length is 30days, I had unprotected sex on 6th, 7th, and 12th of november, and I used contraceptive pill (postinor) some hours after the sex, could I be pregnant?
You had sex during your fertile days so the chances of pregnancy would be high. It is important to know whether you took the Postinor each time you had sex?
I have my first last day menstruation last Oct.17 till 22; a cycle of 21 days I try menstrual cycle calculator.com and it says that my next period is Nov.7. But my period did not come that day… I’m so happy coz I want to get pregnant but now Nov.12. I have my monthly period…pls help me to know more about this thanks.
It is normal for a menstrual cycle to be increased or decreased by a few days without a warning. It’s a normal occurrence that you should not be too worried about. Continue to monitor your cycle to determine if you now have a 26 days cycle instead.
I had sex with my husband 3 days after my period Nov 15 22 and 29. I want to get pregnant badly..Do you think I’m fertile on those days? When is my next period.
Thanks and God Bless.
please i have been encountering this problem for many years now but i don’t how to go about it.let me start with this year January 2015……………. on January my menses was on the 19th January ,February 12th,March 8th, April 3rd,May 26th, June 21st, July 17th, August 13th, September 12th, October 6th, and same October 30th . please what is my cycle ? Help me out
The menstrual cycle starts on day one of the bleeding to day one of the next. On average, the cycle lasts for 28 days, but it’s normal to have it longer or shorter. So if one period started on July 10 and the next one started on August 5, then you that person would have a 26 days. This is so because there are 26 days between the first and second period. Use this explanation to Your period comes on the 3rd of each month so count the number of days beween those dates. Your period is approximately 26 days, some months it is about 25 days; practice by calculating it yourself, Read this article http://womanjunction.com/menstrual-cycle-calculating-manually/ for more information.
pls will someone get pregnant if she had sex on the first day of menstruation and on the last day?
Hi
My last period is October 15-20, but till now I have not seen my period yet, . Am I pregnant?
Please reply please thank you
Hi, You need to take a pregnancy to find out or visit your doctor.
The last time I had sex was September 28, 2015, my period was supposed to start on October 17, 2015 . How my weeks am I pregnant?
What was the date of your September period? This is needed to provide an accurate response.
Hi I’m Julia, saw my period last 1st Oct 2015 and I had unprotected sex from 11th of October to 17th October and till now I’m yet to see my period, can I be pregnant?
Your chances of being pregnant depend on whether you were fertile on or around the date that you had sex. It is important to know the number of days in your menstrual cycle and whether you have regular or irregular periods. This information is needed to provide you with the most accurate response.