You know roughly when you ovulated, from a positive ovulation test, a temperature rise or the way your discharge changed. Now you want to know when your period will come, or when a pregnancy test will be worth taking. Count 14 days from the day you ovulated. That’s the usual answer, and the tables below do it for every day.
How many days after ovulation does your period start?
Usually about 14. The NHS says the time from the release of an egg to the start of a period is around 10 to 16 days. The US Office on Women’s Health gives a wider range, from 7 days to 19.
That stretch after ovulation is called the luteal phase. Cleveland Clinic says it’s usually 12 to 14 days and calls anything from 10 to 17 normal. It tends to stay about the same length for you from one month to the next. The part before ovulation is the part that stretches or shrinks, which is why a late ovulation means a late period.
If I ovulated on day 17, when will my period come?
Find the cycle day you ovulated on and read across. Day 1 is the first day of your last period, and the guide to what counts as day 1 helps if you aren’t sure. “Due” is 14 days after ovulation. “Could start” is the NHS range of 10 to 16 days. The due day is also the first day a standard pregnancy test is reliable.
| Ovulated | Period due | Could start |
|---|---|---|
| Day 10 | Day 24 | Day 20 to 26 |
| Day 11 | Day 25 | Day 21 to 27 |
| Day 12 | Day 26 | Day 22 to 28 |
| Day 13 | Day 27 | Day 23 to 29 |
| Day 14 | Day 28 | Day 24 to 30 |
| Day 15 | Day 29 | Day 25 to 31 |
| Day 16 | Day 30 | Day 26 to 32 |
| Day 17 | Day 31 | Day 27 to 33 |
| Day 18 | Day 32 | Day 28 to 34 |
| Day 19 | Day 33 | Day 29 to 35 |
| Day 20 | Day 34 | Day 30 to 36 |
| Day 21 | Day 35 | Day 31 to 37 |
| Day 22 | Day 36 | Day 32 to 38 |
| Day 23 | Day 37 | Day 33 to 39 |
| Day 24 | Day 38 | Day 34 to 40 |
Ovulating on day 21 puts your period around day 35. That’s about the longest cycle the NHS calls normal, which is 35 days. Ovulating later than that means a longer cycle than usual. Once or twice that’s nothing to worry about, but if it keeps happening, the guide to irregular periods covers the common causes.
I ovulated on the 11th. When will my period come?
If you think in dates rather than cycle days, use this one. It counts in a 31-day month like January. After a 30-day month, any date that rolls into the next month comes a day later. After February it comes three days later.
| Ovulated | Period due | Could start |
|---|---|---|
| 1st | 15th | 11th to 17th |
| 2nd | 16th | 12th to 18th |
| 3rd | 17th | 13th to 19th |
| 4th | 18th | 14th to 20th |
| 5th | 19th | 15th to 21st |
| 6th | 20th | 16th to 22nd |
| 7th | 21st | 17th to 23rd |
| 8th | 22nd | 18th to 24th |
| 9th | 23rd | 19th to 25th |
| 10th | 24th | 20th to 26th |
| 11th | 25th | 21st to 27th |
| 12th | 26th | 22nd to 28th |
| 13th | 27th | 23rd to 29th |
| 14th | 28th | 24th to 30th |
| 15th | 29th | 25th to 31st |
| 16th | 30th | 26th to 1st |
| 17th | 31st | 27th to 2nd |
| 18th | 1st | 28th to 3rd |
| 19th | 2nd | 29th to 4th |
| 20th | 3rd | 30th to 5th |
| 21st | 4th | 31st to 6th |
| 22nd | 5th | 1st to 7th |
| 23rd | 6th | 2nd to 8th |
| 24th | 7th | 3rd to 9th |
| 25th | 8th | 4th to 10th |
| 26th | 9th | 5th to 11th |
| 27th | 10th | 6th to 12th |
| 28th | 11th | 7th to 13th |
| 29th | 12th | 8th to 14th |
| 30th | 13th | 9th to 15th |
| 31st | 14th | 10th to 16th |
When can I take a pregnancy test after ovulation?
The NHS says most tests work from the first day of a missed period. With a 14-day count, that’s 14 days after you ovulated. Some very sensitive tests can pick up a pregnancy a few days before that. A positive result is almost always right. A negative one taken early is less reliable, because the pregnancy hormone may not have built up yet.
If you get a negative result and still have no period, the NHS says to wait a few days and test again. If you’re not sure when you ovulated, the pregnancy test calculator works from the date you had sex instead. It uses the NHS rule of at least 21 days after unprotected sex.
Why your period might not match the table
The table is only as good as your ovulation date. Ovulation tests show a hormone surge, and you usually ovulate a day or so after it. A temperature rise shows up after ovulation has already happened. So your real ovulation day can be a day off from the one you wrote down, and the due date moves with it.
Sometimes the gap itself changes. Cleveland Clinic says a luteal phase under 10 days is short, so a period that keeps arriving within a week or so of ovulation is worth raising with a doctor, especially if you’re trying to get pregnant. A period more than 16 days after a confirmed ovulation is past the NHS range. Take a test, and if it’s negative, the late period calculator shows how late you are and when to see a GP.
The cycle day by day guide covers what you might feel in the days between ovulation and your period. To count the other way, from your period to your next ovulation, use the guide to when you’ll ovulate.
How Plum predicts your next period
We make Plum, a period tracker app for iPhone, so this part is about our own app. You can log an ovulation test as positive, negative or unclear on any day, so the result sits next to your period dates. Plum’s predictions don’t use those results, though. It predicts your next period from the start dates you log, then counts back to show your likely ovulation day and fertile window. Both are free.
So if you test, use the table above for this month and let Plum learn your cycle over time. When your period comes, log the day it starts and the next prediction moves to match. Plum shows no ads and never sells personal data.
