Thanks! Well, it can work for both, the core items don't change and the way to play Jax is mostly the same.

Pretty cool guide, but one question : Is he scaled on 5v5 or 3v3? I've heard Jax is a bit OP in 3v3... ^^"

Yeah, I was beginning to think the same so i modified my stuff, I still recommend the HexDrinker aginst powerful casters and I kept the Guinsoo, because I think it's really important to get some attack speed as early as you can without forgetting to also get some AD and AP, which give you more life, but I took back the Sword of the Divine to replace it with the Wit's End, which appears to me to be really more useful with the AD and MR it adds + its good attack speed.
I also corrected my Masteries, I did it too fast the first time x)
Thank you for your comment, it helped me updating this build ;)

think that Hexdrinker shouldnt be a core item. Its just a choice if you are facing carrys ap like [vladimir] or [karthus] because his utimates. Anyway, i allways build my jax with a nice survival items, so you can get all your buff from your Ult and Guinso without diying before. Once I try [hexdrinker], and it works perfect on jax.
Same happend with Sword of Divine... its passive is kinda similar to our ultimate (i allways say that guinso+sword of divine = jax ult) but i use just in certain situations: playing against another [jax], a [nidalee] or a [sivir] because they can dodge. Even works vs [teemo]`s blinding darts.
ON masteries you use lethality but you dont have Crt items... :/