Characters often do not have a canon age because of how the timeline progresses.

Probably in his late 20s. Maybe early 30s.

Vaguely in his Early 30s.

The best estimation I can give is within a few years of Dick Grayson, other than that probably mid to late 20s to early 30s

I always though Wally was a year or 2 older than Dick. I personally think dick is about 27-29, so I think Wally is maybe like 29-31. Just my opinion.