Antonym of expired
Colloquially I would tend to use "in date(s)." For example:
The 2% milk is expired, but the whole milk is still in dates.
There are other antonyms, but they are not exact antonyms and so will only apply to certain domains/subjects:
- valid
- fresh
- good
The last one seems odd, but is in fact quite common:
Q: Has that milk expired?
A: No, it's still good.
And then of course there is the technically correct answer that I've never heard in common usage:
- unexpired