Three options, two deadlines
- Levonorgestrel (Plan B, Levonelle, generics): up to 72 hours. Most effective in the first 24. Over the counter.
- Ulipristal acetate (ella, ellaOne): up to 120 hours, and more effective than levonorgestrel throughout. Pharmacy in the UK, prescription in the US.
- Copper IUD: up to 120 hours, over 99% effective, and it keeps working as contraception for years. Needs a clinic appointment, so call today.
The calculator converts your date and time into each deadline in your local time zone and counts down to it, so "72 hours" becomes a day and a time you can plan around.
After the window
If it has been more than five days, emergency contraception will not help. Take a test when it becomes meaningful; the when to take a pregnancy test calculator gives the date from the day of sex. To see how likely pregnancy was from that day in your cycle, try the could I be pregnant calculator. And if a missed pill was the reason, the missed pill calculator tells you what to do about the rest of the pack.
Frequently asked questions
How long after unprotected sex can I take the morning after pill?
Levonorgestrel (Plan B, Levonelle) is licensed for up to 72 hours, three days, and works best in the first 24. Ulipristal acetate (ella, ellaOne) works for up to 120 hours, five days, and stays effective across the whole window. The copper IUD can be fitted up to five days after sex and is the most effective option at any point.
Which morning after pill is best?
Ulipristal is more effective than levonorgestrel at every time point, and the difference grows after 72 hours. Levonorgestrel is easier to get, cheaper, and fine within 24 hours for most people. If you weigh over about 70 kg or have a BMI over 26, ulipristal or the copper IUD is preferred because levonorgestrel may be less effective.
Does the morning after pill work if I have already ovulated?
The pills work mainly by delaying ovulation, so they are much less effective if ovulation has already happened. The copper IUD works after ovulation too, which is one reason it is the most effective option. If you are near mid-cycle, ask about the IUD.
Can I use the morning after pill more than once in a cycle?
Yes, it is safe to take it more than once, although it is less effective than regular contraception and can make your next period earlier or later. If you find you need it repeatedly, a regular method will protect you better.
What if I vomit after taking it?
If you vomit within two hours of levonorgestrel or three hours of ulipristal, the dose may not have been absorbed and you need to take another. A pharmacist can supply a repeat dose.
These calculators give estimates based on cycle averages and standard formulas. They are for general information only and are not medical advice. For anything concerning your health or pregnancy, talk to a qualified healthcare provider.