How many gallons are in a barrel?

There are 31.5 fluid gallons in one fluid barrel. There are 42 gallons of oil in one oil barrel and 26.24975569 dry gallons in one dry barrel.

Refineries in the United States produce 19 gallons of motor gasoline from every barrel of oil. The rest of the barrel is used to make distillate and residual fuel oils, jet fuel and petroleum coke. Liquids that are shipped in barrels include wine, whiskey, brandy, vinegar and beer. Traditional wooden barrels were largely replaced in the 19th century by corrugated fiberboard boxes for dry items. Beginning in the mid-20th century, most fluids were packed in steel drums.