Ovulation Calculator:
When Do I Ovulate?

When are you most fertile?
Find out with our free ovulation calculator:

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If you’re TTC (or adamantly not trying to conceive), knowing when you’re ovulating can be indispensable information.

Try our ovulation calculator above to see when is ovulation for you to figure out your best chances to get pregnant (or safe days for not getting pregnant).

What is my ovulation date?

When do I ovulate?For most women, ovulation tends to happen 14 days before the first day of your last period.

This is also usually the case for longer or shorter periods ‒ the average menstrual cycle is 28 days long, but it can be anywhere from 21-45 days long.

So if you’ve just started your period, your previous ovulation date was around 14 days ago.

It’s hard to say exactly when your next ovulation date will be without knowing how long your menstrual cycle usually lasts, as for a person with a 21-day cycle, their ovulation date will be different from a person with a 35-day cycle.

How can I calculate my ovulation date?

So, when do you ovulate?You can calculate your next ovulation date from the first day of your last period and the length of your average cycle.

It can take a bit of mathematics, so it’s best to use our ovulation predictor above to figure out when your next ovulation date will be.

But when is ovulation for people with irregular periods?

Well, you can use our ovulation calculator for irregular periods, but you may not get an entirely accurate result.

If you want to find out when is ovulation for you with an irregular period, an ovulation test might be the best option.

When to take ovulation test calculator?

So when is best to use an ovulation calculator?

Well, if you’re tracking your periods, you can take it at any time ‒ all you need is the date of the start of your last period and the average length of your menstrual cycle.

But if you’re not tracking your periods, it might be best to wait until your period starts so you can enter the right date for the most accurate ovulation predictor result.

How accurate is ovulation calculator?

There’s no such thing as a 100% accurate ovulation calculator.

Hormones are changing pretty much all the time, and ovulation can be triggered by those fluctuating hormone levels.

So while an ovulation calculator can provide you with a general fertile window ‒ the time that you’re most likely to be ovulating ‒ it can also be a good idea to be on the lookout for other ovulation symptoms, such as:

When to start tracking ovulation?

It’s totally up to you when you start using an ovulation tracker.

Some people use an ovulation calculator to figure out safe days for not getting pregnant ‒ although most of the time, for people with ovaries, there’s always a chance of getting pregnant, no matter how small.

Other people use an ovulation predictor to calculate the best days to have sex to get pregnant ‒ while you’re ovulating, the chances of getting pregnant can be significantly higher.

And other people use an ovulation calculator because they simply like to know what their body’s doing during their menstrual cycle ‒ it can explain a lot!

Which day of ovulation is best to get pregnant?

So, when are you most fertile?

During your fertile window!

You can use our fertility calculator to figure out your most fertile dates, as this is when you start ovulating and the days following ovulation.

Here’s also a handy breakdown for an average 28-day cycle (although if your cycle is more or less than 28 days, our ovulation calculator can help):

  • Day 1: Less than 1% chance of getting pregnant
  • Day 2: Less than 1% chance of getting pregnant
  • Day 3: Less than 1% chance of getting pregnant
  • Day 4: Less than 1% chance of getting pregnant
  • Day 5: Less than 1% chance of getting pregnant
  • Day 6: Less than 1% chance of getting pregnant
  • Day 7: Less than 1% chance of getting pregnant
  • Day 8: Around 3% chance of getting pregnant
  • Day 9: Around 6% chance of getting pregnant
  • Day 10: Around 9% chance of getting pregnant
  • Day 11: Around 18% chance of getting pregnant
  • Day 12: Around 27% chance of getting pregnant
  • Day 13: Around 33% chance of getting pregnant
  • Day 14: Around 42% chance of getting pregnant
  • Day 15: Around 20% chance of getting pregnant
  • Day 16: Around 8% chance of getting pregnant
  • Day 17: Less than 1% chance of getting pregnant
  • Day 18: Less than 1% chance of getting pregnant
  • Day 19: Less than 1% chance of getting pregnant
  • Day 20: Less than 1% chance of getting pregnant
  • Day 21: Less than 1% chance of getting pregnant
  • Day 22: Less than 1% chance of getting pregnant
  • Day 23: Less than 1% chance of getting pregnant
  • Day 24: Less than 1% chance of getting pregnant
  • Day 25: Less than 1% chance of getting pregnant
  • Day 26: Less than 1% chance of getting pregnant
  • Day 27: Less than 1% chance of getting pregnant
  • Day 28: Less than 1% chance of getting pregnant

When is peak ovulation?

If you want to know when are you most fertile, “peak ovulation” is the term that you’re looking for.

This is when you’re at your most fertile in your menstrual cycle ‒ the day when you start ovulating.

In the days before and following your peak ovulation date, your chances to get pregnant will still be higher, although they will be lower.

Most women’s peak ovulation date tends to be about 14 days before the first day of their period.

How long is ovulation window?

Your ovulation window usually lasts about 24 hours ‒ when your ovaries release an egg ‒ although this can be up to 72 hours if they release more than one egg that cycle.

This is a different from your fertility window, which includes your ovulation peak (when your ovaries release an egg) and about 3-5 days around your ovulation peak, as your chances of getting pregnant are increased at that time.

However, the ovulation window is the time with the highest chance to get pregnant, as the percentage chance drops straight after that date.

If you’re not sure when your ovulation window is, use our quick, free ovulation calculator to work it out.

Can I get pregnant 7 days before my period?

Yes, you can get pregnant 7 days before your period ‒ there’s around less than 1% chance, but there’s still a chance you can get pregnant.

Can I get pregnant 3 days before ovulation?

Yes, you can get pregnant 3 days before ovulation ‒ about 3 days before ovulation, your chances of getting pregnant are about 9-18%.

Can I get pregnant 2 days after ovulation?

Yes, you can get pregnant 2 days after ovulation ‒ you have about a 1-20% chance of getting pregnant.

➡️ Dig deeper: Can You Get Pregnant After Ovulation?

I have a 35-day cycle when do I ovulate?

Most women tend to ovulate 14 days before the first day of their period.

So if your cycle lasts 25 days (with day one being the first day of your period), you may be ovulating on around day 21 of your cycle.

If my period lasts 3 days, when do I ovulate?

Usually, the ovulation window is 14 days before your period starts (usually on day 14 for a 28-day cycle), as it’s calculated from the first day of your period rather than how long your period lasts.

However, if your period is irregular or it lasts more or less than 3-5 days, your ovulation window may be a different date, so an ovulation test may give you a more accurate result.

How do you calculate your most fertile days?

First, it helps to know when your peak ovulation date is ‒ the day that your ovaries release an egg (maybe more than one).

The days leading up to and days following ovulation are your most fertile days in your menstrual cycle.

How many days after period do I ovulate?

It depends ‒ your ovulation window is calculated from the first day of your last period and the length of your average cycle can impact when you ovulate.

But for the average 28-day cycle, with a period lasting 4 days, you can expect to be ovulating about 10 days after your period stops (at about day 14 of your cycle).

When do you ovulate after period?

Usually, when working out when do you ovulate, you look at the first day of your period, rather than the last, as some periods can last 1 or 2 days longer or shorter as part of a regular menstrual cycle.

So for a 28-day cycle, most women ovulate on day 14 ‒ around 8-10 days after your period.

How many days after your period can you get pregnant?

You can actually get pregnant at any point in your menstrual cycle.

Although outside of your fertile window, the chances of getting pregnant are less than 1%.

It also depends on how long your menstrual cycle usually lasts, as a regular cycle can be anywhere from 21-45 days long, which would mean that your ovulation date could be quite different from someone with a longer or shorter cycle.

Can I get pregnant 5 days after my period?

Yes, you can get pregnant 5 days after your period.

In fact, in an average 28-day cycle, with a period lasting around 3-5 days, 5 days after your period stops could well be into your fertile window.

But to get your personal ovulation window, use our free ovulation calculator above!

Can I get pregnant 10 days after my period?

Yes, you can get pregnant 10 days after your period.

For an average 28-day cycle and a 3-5 day-long period, 10 days after your period ends could be right in the middle of your fertile window ‒ maybe even on your ovulation peak.

But for the most accurate ovulation window for you, feel free to use our ovulation predictor.

How long is ovulation?

Ovulation usually lasts for 24 hours ‒ the time it takes for one of your ovaries to release an egg.

However, for some menstrual cycles, two (or more) can be released, meaning your ovulation window (and, as a result, your fertile window) is longer than usual.

So, for some cycles, ovulation could last as long as 72 hours.

Do you only ovulate for one day?

Usually, yes, you ovulate for one day per cycle.

However, sometimes, your ovaries can release more than one egg, which can mean that ovulation lasts for more than 1 day.

How long does peak ovulation last?

Generally speaking, peak ovulation lasts for <s>24 hours</s>, but it can last longer if your ovaries release more than one egg.

How many hours does ovulation last?

On average, your ovulation peak (or ovulation window) lasts for 24 hours, but it can be anywhere from 12-to 72 hours , depending on how many eggs your ovaries release that cycle.

What are the signs of ovulation?

So aside from using an ovulation calculator, how can you tell if you’re ovulating?

As it turns out, there are a few symptoms of ovulation, but, typically enough, some of them are pretty similar to period symptoms:

  • Cervix pain
  • Bloating
  • Your basal temperature falls - and then rises
  • Nausea
  • Increased sex drive
  • Fatigue
  • Tender breasts
  • Spotting
  • Diarrhea
  • Back pain
  • Hot flashes
  • Bladder pain
  • Dizziness

Can you feel yourself ovulate?

Some women can feel themselves ovulating ‒ not quite feeling their egg traveling from their ovaries, but there are other symptoms of ovulation.

If you think you might be ovulating, keep track of how you’re feeling and use our ovulation calculator to see if you could be feeling your ovulation peak.

Does ovulation happen in the morning or night?

The general consensus is that you can ovulate at any point in the day ‒ morning, noon, or night, but there aren’t any verified studies to confirm this.

In fact, the medical director of the Family Fertility Centre in Adelaide, Australia, Dr. Marcin Stankiewicz, suggested that the seasons may be responsible for dictating what time of day you ovulate.

He suggested that some people ovulate in the morning during the spring and summer months, and in the evening during fall and winter.

However, we’ve not found any studies to support this claim.

What is considered early ovulation?

Since the average ovulation is about day 14 of a 28-day cycle, early ovulation can be classed as ovulating on <s>day 11 or earlier</s>.

However, it depends on how long your average menstrual cycle is, and if you have regular periods, as both of those can impact when you ovulate.

For example, someone with a 21-day regular cycle may find that ovulating on day 11 is perfectly normal and won’t impact their chances of getting pregnant, but ovulation on day 11 of a 35-day cycle could be a sign that getting pregnant may be a challenge.

Why do I ovulate early?

There can be many factors that can impact when you ovulate in your menstrual cycle:

  • Stress
  • Illness
  • PCOS (polycystic ovaries syndrome)
  • Birth control pills
  • Weight
  • Menopause or perimenopause
  • Medications
  • Breastfeeding
  • Age
  • Endometriosis
If you think you may be ovulating early, it can be worth paying a visit to your doctor, just in case.

What is considered late ovulation?

Late ovulation is officially classed as ovulating on or after day 21 of your menstrual cycle.

But if you have a longer cycle, lasting anywhere from 35-45 days, ovulating on day 21 of your cycle may be perfectly normal and not negatively impacting your fertility.

Why do I ovulate late?

Late ovulation can be caused by many of the same things as early ovulation ‒ these can all cause late or irregular ovulation:

  • Stress
  • Illness
  • PCOS (polycystic ovaries syndrome)
  • Birth control pills
  • Thyroid issues
  • Weight
  • Menopause or perimenopause
  • Medications
  • Breastfeeding
  • Age
  • Endometriosis

What are the chances of getting pregnant when not ovulating?

So what are the chances of getting pregnant when not ovulating?

Well, there’s always a chance of getting pregnant at any point in your cycle, no matter how slim.

But when you’re not ovulating, or you’re not in your fertile window (the days around your peak ovulation day), your chances of getting pregnant are less than 1%.

Can you ovulate without a period?

If you’re on birth control or you have irregular periods, you may be asking, can I ovulate without period?

The answer is yes, you can ovulate without a period, and you can have a period without ovulating.

However, it is rare.

If your periods have stopped and you’re not sure why, please visit your doctor, just in case.

Do you ovulate on birth control?

Not usually, no.

More often than not, the way that birth control pills work is to block your ovulation from happening at all, thanks to the hormones in the pill.

However, birth control pills aren’t 100% guaranteed to prevent pregnancy ‒ there’s around a 1% chance of getting pregnant if you take your pill regularly, and anywhere up to a 9% chance if you’re not quite as regular.