(I'm) doing okay.
1. Inf. I'm just fine. Bob: How you doing? Bill: Doing okay. And you? Bob: Things could be worse. Mary: How are things going? Sue: I'm doing fine, thanks. And you? Mary: Doing okay.
2. Inf. I'm doing as well as can be expected.; I'm feeling better. Mary: How are you feeling? Sue: I'm doing okay—as well as can be expected. Tom: I hope you're feeling better. Sally: I'm doing okay, thanks.