never (been) better

never (been) better

As good, happy, healthy, contented, etc., now as one has ever been before. Used as a response. A: "How are you feeling, Tom? I know that flu really took it out of you last week." B: "Never better! Just needed a few days of rest, relaxation, and chicken noodle soup." A: "How's business lately?" B: "Never been better. We're getting more orders than we can keep up with, which is a great problem to have."
See also: better, never
Farlex Dictionary of Idioms.

(I've) never been better.

 and (I've) never felt better.
a response to a greeting inquiry into one's health or state of being. Mary: How are you, Sally? Sally: Never been better, Mary. How about you? Doctor: How are you, Jane? Jane: Never felt better. Doctor: Then why are you here?
See also: been, better, never
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • never been better
  • never felt better
  • happy as the day is long
  • (as) happy as the day is long
  • (as) happy as a lark
  • happy as a lark
  • those were the days
  • (as) happy as a pig in clover
  • clover
  • happy as the day is long/as a clam/as Larry