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 March 3, 2016 and it lasts until March 6,2016. I had sex with my boyfriend on March 19th and 20th. My period came back on the 29th and went off the 30th. Could I be pregnant?
From November 2015 through February 2016 I had no period. I really thought I was pregnant. And was excited, and praying everyday for our miracle child to finally bless our family. Took tests ,came back negative. 2 weeks later got my period. I cried ,and I think my fiancé whom I’ve been with for 10 year’s was just as upset. It was_is still kinda hard wanting something so special, innocent ,beautiful such as a child. We are still young and actively trying. So if you still are reading this please pray for me, us , our future family. I have never felt a pain so deep in my flesh ,and soul like this. I hope no one does. I still cry, I still hurt, I still need and yearn for my baby. We are still without child. But we pray and are still hopeful one day soon we will be blessed like so many others worthy or not. Please, I ask you again pray for me as I pray for everyone in the world every night. Thank you if you do. Bless you too. Please no nasty comments, hate mail or hateful thoughts. I only wish the best for everyone. I only wish one day to be able to love and hold my child as you may. Dear Lord, Please ,Please, Bless us with a child of God to be Healthy, Smart,and Beautiful. Hear me. Heal me. Help me.
Bless Us With Child! EricaM. Thank you!
When you see clear jelly like discharge when you wipe then you are ovulating and need to get busy making your baby! It worked for me. Got pregnant on our first try! Good luck!
Hello Erica. I sympathize with you. Will pray for you. Its very important that you and your fiance consider getting married. In a covenanted relationship of marriage under God, you will see God work miracles in your life. It is always the best environment for godly living and child upbringing. Blessings. With Love (no wrong intended)..
May Jesus remember and bless you with the fruit of the womb. Amen
Before the end of this year, you will hear the cry of a child in your home. God’s promises for you are real.
Hi, I’m trying to have baby as well I had a miscarriage in August saddest day of my life:( but I’m taking these fertility pills called Conceive Easy look into it…I see a lot of positive reviews!!!! Best of luck to you and yours and I hope you will get your miracle baby.
Hello, I wanted to know if it’s possible that I could be prego. I last had my period March 18 of this year and had intercourse with my partner Friday April 1st the 3rd and 4th of this same month. I have been feeling cramps lately, but, yet wonder if I could be pregnant. I have not taken a pregnancy test because I wanted to wait and see if my period appears. How are my chances?
Hi Franchelina,
The chances are good yes. But do wait until 10 days after your next period date. Cramps may be due to other reasons too, and you don’t want to get all your hopes tied up to this. All the very best!
I had my period March 7. My cycle is 29 days. I had sex the 13th, 17th 21st and 22nd. Could I have gotten pregnant the 13th?
You were most fertile period on March 20 to 24, 2016. Our next menstrual period is expected to start on April 05,2016. You could not have conceived on the 13th.
For the month of February my period was 4 days late but it finally came on February 28 and ended March 2. My fiance and I had sex all throughout March. Again in March my period was 6 days late and it finally came on April 2nd and ended on April 6th, but it was very very light. Never had a light period. Should I take a test or should I just wait until my next period and go from there?
Yes, wait for your next period and take it from there.
Okay. Thank you very much Steffy.
My last period came on March 18 and it lasted for only 2-3 days and I still haven’t seen my period for April but on the 12th of April I spotted a little and then that’s it. I’ve been feeling cramps but no period. Can I be pregnant?
I had my period last march 9, 2016 and i have a 30 day cycle period i have unprotected sex last april 2, but until now still waiting for my period. Is it possible that im pregnant?
Hi Lara, yes there is a possibility. If you have not got your period till now, please take a pregnancy test. ATB!
Alekya
I have sex on 21 st day of my periods is there any chance to get pregnancy?? My last period is on March 13
It was April 02 the last pill I take 3,4,5 I never take the pills. then 06 April I take 2 pills in my new pack, but 04 april I have sex with my bf using condom but accidentally lift off the condom in my bf was ejaculate inside my vagina and that day is my fertile day. It is possible I got pregnant even I continue the pills in the different pack?
Hi Rose, yes there is a possibility. Please continue the pills.
The first day of my last period was March 15 2016….I still have not had my period for April, was wondering when I should be getting it?
Same here. Other factors can play a role as to why us women can experience late periods including possibly stress, illness, birth control, medicines, many other things. As for me, I’m just going to wait and see if I’ll be menstruating by the end of this month.
I last had sex on Sunday, April 10th and My period was due to start today. I have been cramping but no blood shed yet. Is it possible I can be pregnant or just that my period is late?
It could be that your period is just late. Give it another week to see if it will come.
i had my previous period on 9th of march and it lasted for 5 days.another one was on 8 of April and it lasted for 5 days also. please what is the length of my cycle and what day am i to expect the next period? also in my last period which was on 8 to 12 april and i had sex on 13 of April can i get pregnant?
You have to be ovulating to get pregnant! So when u see clear jelly like discharge u need to get busy.. You only have 12 hrs to do so. Worked for me. Good luck!
Hi, I am worried. My last period was March 11- March 14 2016. My period has not come yet. Sometimes I’m irregular and I don’t know how to calculate if my period is 28 days cycle or 35. I took a pregnancy test last Monday, but its negative. Kindly answer my question what should I do. I had unprotected sex with my husband on 30 march. Is it possible that I am pregnant?
Hi Moneth, it’s too soon to worry and also too soon for a pregnancy test to work properly. Please wait till 25th April. If you don’t get your period by then, then take a pregnancy test. ATB!
Hello, I had my menstruation on March 25, 2016 and my boyfriend and I have sexual intercourse on April 5, 2016. Is it possible for me to get pregnant?
The chances of you being pregnant depend on whether you were ovulating at that time. If you have a regular 28 days cycle then the chances of you getting pregnant would be low.
Hi i started my period on the 16th of march and i finished it on the 19th of march.my cycle length is 27days.pls am not sure when am suppose to see my next period.i want to know if am pregnant pls
Hi Anu, by this info., you should have seen your period around 10th May. If you have not got it by today, please take a pregnancy test. All the best!
Hi. I started my periods on the 11 April 2016 and I took 5 days, so my last day is on Friday the 15th of April 2016. If I had sex on the 16th can I get pregnant? Or when must I?
Yes, it is possible but it depends on the number of days in your menstrual cycle. If you have a 28 days cycle, you can ovulate on the 14th day like the average female.