How much damage does a punch deal?
A person in my party punched a bartender and I didn't know how to calculate how much damage it would deal. Does anyone know what die I use to calculate this and if any modifiers increase the damage?
Who voted this question down and didn't even tell the OP why? Come on folks! Likely the question was voted down because the answer is easily found with a google search, but hey, we all miss stuff like this, I am sure you are not the only one. Also, this is different than how it was handled in previous editions, such as 3.5e which had your unarmed strike damage change with creature size. I personally feel like this is an okay question.
Does it even matter? If the bartender is important for the story, you might as well say _"Your fist hurts, the bartender seems unimpressed"_, just so the story doesn't die. Or, if the bartender isn't interesting in any way, you might just let him go down unconcscious like most unimportant, normal people would. There's no urgent need to roll whether you were able to kill him, really... it's a _bartender_, not the King of Orcs.
1 + Str modifier, as the SRD says
Instead of using a weapon to make a melee weapon attack, you can use an unarmed strike: a punch, kick, head--butt, or similar forceful blow (none of which count as weapons). On a hit, an unarmed strike deals bludgeoning damage equal to 1 + your Strength modifier. You are proficient with your unarmed strikes.
Some features (monk, etc) may change the amount of damage caused.
The current PHB errata from WoTC updates what's in the PHB on page 195, and states the unarmed strike proficiency as shown in the SRD. It also states:
Weapons (p. 149). Unarmed strike doesn’t belong on the Weapons table