# what does “I'll be back in 3 days” mean?

I'll be back in 3 days

Does it means

I'll be back after 3 days.

or

I'll be back within 3 days.

or

I'll be back 3 days later precisely.

I agree with Maulik's paraphrase: in three days generally means three days from now. However, I'd start from today and count three days on the calendar, assuming the person would return on that third day, not on the day after that third day.

I also think there's a little bit of wiggle room, depending on the statement and the context. For example, if an employee of mine says, "I'll have that report ready in three days," I'd interpret that to mean, "I'll have it done within three days, maybe even a little earlier." The word "approximately" is also often implied. If a renovation team says, "The renovation will be done in three months," then "give or take a few days" might be implied. Such variations don't seem as likely, though, when someone is talking about a return date that is only three days away.

If someone left at 3 o'clock saying, "I'll be back in three hours", I would expect them to be back at or around 6 o'clock: the duration of the trip is three hours.

The same applies to days: if someone tells me, at noon on Monday, that they will be back "in three days", I will expect them back sometime on Thursday, three days from Monday. The duration of the trip is approximately three days.

Really, the time of day during business hours should have no effect on day counting. "I'll be back in 3 days" or "come back in 3 days" really should be counting from the day after today as day-1. Say today is just past midnight on Monday and someone says "come back in 3 days", when should you go back? The third day after today - Thursday. Since today has already begun, it doesn't count in the solution because it is known that there's no resolution in that day. But think of it again this way, "come back the next day" is 1 day, which could be seen as day 1 because the day you discover that you need to come back was the day you thought your need would be taken care of. As much as we wanted it to be 3 days inclusive of the day we heard "come back in 3 days", we can't deny that the phrase can very well be rephrased as "come back 3 days from today. "

You have mentioned the number of days. And thus, it means 'three days from now'. Say, if you are going on Sunday night, you'll be back after 3 days (Monday, Tuesday, and Wednesday) i.e. on Thursday.

[Note: I excluded Sunday as that's the day of 'going'.]

after a particular length of time

It will be ready in a week's time (= one week from now).
She learnt to drive in three weeks (= after three weeks she could drive).

• Funny - if on a Sunday someone told me they'd be back in three days, I'd assume they were coming back on Wednesday (i.e., on the third day). – J.R. Nov 20 '15 at 9:31
• Aw.. '..on a Sunday...' It looks a wonderful question to me! @J.R. – Maulik V Nov 20 '15 at 9:37