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





hy dear how are you doing. please I had my last menstruation on the 6th of July when is my most fertile period and when is my next period coming. in June too I had my flow on the 6th.thanks
Hello Esther! Here are your most fertile dates for the next 6 months. This is based on a 30 day cycle so be sure to make sure the first day of your period is 30 days from the last and these dates should be of much assistance for you.
Aug 18 – 23
Sep 17 – 22
Oct 17 – 22
Nov 16 – 21
Dec 16 – 21
Jan 15 – 20
I was on depo and quit taking it. My last Shot was Feb 24th next one was due May 19th. I quit taking it because I was bleeding all the time and wanted my periods to regulate on their own. May I had a cycle, June 11th I had a cycle. July no cycle at all. All hpt’s are negative. I’m confused as to what could be going on if I’m not pregnant.
Hello Casey. I would have to recommend you speak with a doctor or professional.
hi I wanted to see if ya ladies can help me
okay so I was supposed to have my period July 5 but got it july,8 and it ended july12 I caulcated my ovulation date and it said the 25 . I had sex with my husband the 19th , 21st 24th and 25th is there a possibility I can get pregnant?… plz let me know if you can help with info thanks
definitely because you had sex on fertile days ,21, 22.23 , 24 would be fertile for you since ovulation is the 25th
Yes! There is a very good chance you conceived. Sperm can live up to a week once inside of you, giving you a better chance on the 19th-24th to prepare for the 25th. Good luck you two!
Hi, I saw my period on the 8th of jully I have sex on the 13th of jully am I on a save side? P
Hello everyone; I really need your advice! So me and my boyfriend have unprotected sex all the time. My first day of my period was July 11,2015 and last for 5days. We had sex on the 15th, 17th,& the 25th of July& to find out he came inside me all times. And when I checked my app it said I was fertile those days,but I’m not for sure what day my ovulation came it’s either the 22nd or 25th. Is there a high chance of me getting pregnant? If so how soon can I test?
Yes there is a good chance you conceived. You can test as soon as the day after your missed period. If you would like to sooner, with First Response you can test up to 5 days before the date of your missed period.
Hi everyone.
I need your help. My period came on the 24-28 of July, i check my violating days and august 5-9. I had unprotected sex on the 3, 5, 6 and 7th. Do you think.i can get pregnant?
I’ve Had My Period On July 3rd, 2015 Last 5 Days ( Normal 26 Day Cycle) But I’m Late……. By 2-3 Days. I’ve Had Sex Multiple Times 2 Days Before My Period Was Suppose To Begin. Since Then I’m Slightly Constipated , Sore Nipples, On And Off Abdominal Pain ( On And Off Through Out The Day), Fullness In The Stomach Area, When I’m Not Moving I’m Sleepy, Backaches, Headaches Every Once In A While And I’m Usually A Cold Person I’ve Been Pretty Hot Lately ……. Could I Be Pregnant?? When Should I Take A Pregnancy Test??
It is no likely to conceive that close to the end of your cycle, but it is also not impossible. At this point most test will work effectively but read the label to be sure.
Please I had my last period on the 2nd of July and it stopped on the 6th. I had sex on the 7th of July, he started by not using condom but I told him we have to use it nd he went for it. But am scared I may be pregnant cause I urinate a lot these days.
Good morning. I had been taking my temperature since April of 2015. This May 23, 2015 my period came on and also I was taking Clomid. In June I ovulated on the 7th. I was having pain and I took the ovulation test and which it came out position.
Since then, my temperature was rising up for 4 days, went down for few days, couple days down, rise up for couple days and then went ALL the way down til June 22, my period came on and also was taking Clomid. Since June 22, my temperature been under 97.00—97.60
I’m not even sure I ovulated. I haven’t been tracking my ovulation tests like that. I take it here and there. I be forgetting to take the ovulation tests to see if I ovulated. I have had been baby dancing with my boyfriend since June 29, July 1,3,4,5,6,7,9,12,13,14,19,20,21,23,26and 27. My cycle day is 34.
My period: 2015
January 4-10
February 7-14
March 29-3
April 9-15
May 23-29
June 22-28
July no period yet
Temperature chart:
June 22, 97.57
June 23, 97.32
June 24, 97.25 (took 100 mg Clomid)
June 25, 97.52
June 26, 97.57
June 27, 97.36
June 28, no period 97.33 (last clomid)
June 29, 97.57
June 30, 97.01
July 1, 97.52
July 2, 97.22
July 3, 97.22
July 4, 97.23
July 5, 97.57
July 6, 97.26
July 7, 97.29
July 8, 97.57
July 9, 97.49
July 10, 97.57
July 11, 97.49
July 12, 97.41
July 13, 97.22
July 14, 98.41
July 15, 97.57
July 16, 97.39
July 17, 97.57
July 18, 97.00
July 19, 97.22
July 20, 97.42
July 21, 97.13
July 22, 97.03
July 23, 97.46
July 24, 97.27
July 25, 97.27
July 26, 98.34
July 27, 97.27
July 28, 97.56
July 29, 97.53
July 30, 97.58 (today temperature)
So my questions is:
1. Have I ovulated?
2. Do my temperature look promising or no?
3. Did I had to much sex?
4. When do I take a pregnancy test?
Please I need help and answer. Thank you.
My menstrual cycle started on the 12th and lasted 3 days, according to the ovulation calculator I was ovulating the 24th – 28th we had unprotected sex on the 27th only once, though. Do I have a chance of getting pregnant? When should I test?
If you have sex on your fertile days, the chances of getting pregnant are high. You can test at least one week after you have missed a period.
You do have a chance of getting pregnant because you had sex within the ovulation time frame. You should wait until you have your expected period. If you test to early you could get a wrong reading, when you do test. Test in the morning, this is when your hormones levels are the highest which will give you the best result
Okay so I had my period on the 8th of June and then did stuff with a guy on the 20th leading into the 21st – took the pill right away and then got my period the next day on the 22nd. I then got my period on the 17th and then had sex with my boyfriend on the 26th. He had a condom on and was super careful and it did not break and he did not ejaculate inside of me. I just have a lot on my plate and I mean my stomach hurts, that is probably from the heat and worrying about school coming up. Otherwise, it has been 5 days and I really do not feel any different.
Based on the precautionary measures that you took (the morning after pill in June and the condom in July) you may not be at a high pregnancy risk. It would also be too soon for you to experience pregnancy symptoms.
Hello Steffy. Hope you are doing well. I am on birth control and had unprotected sex from July 4- July 12. I started my period on July 20 which was 2 days later than it usually starts and I didn’t bleed as much as I usually do. I have been nauseous, had breast tenderness, I’ve had white mucus discharge, tired all the time and moody for about a week. Could I be pregnant?! I took a test and it was negative but I think I took it too early.
You can wait another week to re-take the test. If the symptoms persist, then you need to consult a doctor.
I had unprotected sex on 22 June then on the 23rd June when doing it my period came in the act. I’m now feeling like vomiting, constipation, breast tendency, nausea and sleeps a lot. Could it be that am pregnant?
No your not pregnant when you have your period your releasing the old egg. 12 to 15 days later you ovulate this is when the egg comes down into the utuerus which takes 5 days, nd you can get pregnant in that 5 day span…but remember sperm can live up to 7 days inside you. Your probably just feeling sick because your overthinking about pregnancy. some wome have been known to have false pregnancy. this is when the womens mind believes shes pregnant so much that her body takes on all pregnancy signs but theres no real baby.
I had my period on 26th July 2015. My menstrual cycle is 28 days. When is my ovulation day?.
Thanks,
Liz
You will ovulate from August 07 to 11, 2015. Your next menstrual period is expected to start on August 23, 2015.
Hi steffy . I got my last menstration last june 30 and it end on july 5 .
I am worried if i am pregnant. Usually my cycle is 28 to 30 days . im 2 days delayed my last contact to my bf is july18,thanks i hope i can get the answer thanks
Omg im goin threw the samething. Same dates as your menstrual and i havnt started yet
Hi Steffy I menstruated last June 27-july 2 and had unprotected sex on July 18. I’m already 4 days late. Could I be pregnant? Please help. Thanks.
I cannot determine as I do not know the normal length of your monthly cycle. You can determine this by finding an Ovulation Calculator online. If you know the dates of the beginning of your last 2 periods and how many days apart they were then you will be able to determine the chance of you conceiving on the 18th.
Hi. I had first-time sex it’s not exactly sex just our internal organs got touched no penetration.Even just touched 5 to 10 minutes on June 8th still I didn’t get periods. I don’t have any pregnancy symptoms. My last menstrual cycle also got delayed. Is it possible for me to be pregnant? I am afraid.
Hello Isha. I am not sure I am understanding your situation. But I do not believe you are pregnant.