Do you mean over her entire career as his Padawan? That was several years and she grew by leaps and bounds.
However, even at her introduction in the movie I'd put her comfortably above Ezra. Firstly she's been training since she was 3. Ezra's been less than a year. Ahsoka was even personally trained by the best of the best like Plo Koon and Yoda. Plus she's just got a shit load of feats in comparison to him.
Ezra's Master is himself a Padawan. Ahsoka's basically got him beat in spades. Unless he can summon some of those monsters I guess, lol.
Looks like current Ahsoka beats down Kanan, and Ezra at the same time!
She was a little kid when Anakin trained her. How did she get so good? You could almost believe she'd wipe the floor with Vader, judging by the fact both Kanan and Ezra were good enough to at least hold him off and keep from getting killed, and they can't really handle Inquisitor's..
When Anakin trained her, she was like 12-14, and she was with him for several years, actively fighting in a war. That's the difference between the two. Ezra's a Force Sensitive, street urchin who's getting some basic training from a guy who never finished his.
Ahsoka is one of the best Jedi of her generation, and was trained by several of the best Jedi in history, and fought actively in a war, going on missions like every day for year.s
And Ezra and Kanan were basically getting tested by Vader. His fight with them was effortless and the only thing that saved their life was that walker getting blown up. She might be faster than Vader, but when they fight I see him overwhelming her with raw force and skill.