Currently I think Andre Ward. He has the advantage because he's a lefty fighting orthodox so his jab has that extra zing. Incredibly accurate.

I think when you're talking about jabs and who has the best jab, versatility should always be considered first. Guys like Ward, Wlad, Holmes, ect accomplished so much with the jab. They could use it defensively to back a guy off, to create space or to keep a guy at range, and they could use it offensively to pressure forward and set up combinations and power shots. Guys like that really utilize the jab fully.

One of my favorite jabbers is a guy that never gets mentioned: Roy Jones. There's a good reason he doesn't get mentioned, because he largely abandoned the jab in favour of lead "pot shots", which he could do because he was so goddamn fast and coordinated. But when he wanted to jab, holy shit. With his speed and power he could throw double, triple, quadruple jabs in a nanosecond, and they were quality, snapping, SLICING jabs. And of course he could hook off the jab with a speed and efficiency I've never seen from anyone else. Another cool thing he'd do is change the trajectory of a jab with perfect precision to sneak in through a guard. If a guy had a tight guard, Jones had a way of sneaking that upward spear jab straight through.