Stout vs. Porter

[Jake]

So what's the difference between the two? Anyone?

[Kyle]

wikipedia has a pretty good description:

http://en.wikipedia.org/wiki/Stout

[Jake]

So when i'm drinking a porter or stout of the same ABV, I shouldn't except anything different (from style to style that is)?

[Richard]

Historically, that would be as possible as it is now. The styles overlap, but it's not as one-dimensional as ABV. Go by the BJCP for the most part:

Porter
Stout

[Dean]

So when i'm drinking a porter or stout of the same ABV, I shouldn't except anything different (from style to style that is)?

when you're drinking a stout or porter from the same brewery they won't have the same ABV, the stout (by definition of the word) will be stronger

a stout is a porter, but the distinction between the two is only relevant when the two are from the same brewery ...if not then all bets are off

[Gil Breau]

I always assumed the main difference is the amount of "dry" malt used. ie Roasted Barley, on top of being stronger, but the two may actually be intertwined. So not only are you getting a stronger alcohol kick from the additional malt, but you're doing it with a much dryer aftertaste.

[Richard]

True if you're talking about Dry Stout, not so much with Sweet/Imperial/Foreign Export Stout

The guidelines for Brown Porter (4-5.4%) and Dry Stout (4-5%) are near-identical in their ABV (note that Porter actually goes a little higher), however the porter is more restrained in the quantity of darker malts, as you stated. Dry Stout is SRM 25-40, Brown Porter 20-30, and the IBUs follow suit (30-45 vs 18-35).

Then you have robust porter, which pushes the numbers up yet further: SRM 22-35/IBU 25-50/ABV 4.8-6.5%

To me, the difference from the guidelines seems to be the use of flaked unmalted barley in dry stouts, and other efforts (such as dissolved nitrogen) to make stout:

a fuller, creamier, more “stout” body