There is a difference between the two measurements. 8 ounces is equivalent to 236.59 milliliters, while 250 milliliters is equal to 8.45 ounces. This means that 8 ounces is slightly more than 250 milliliters. When converting from one measurement to the other, it is important to keep this difference in mind so that you don't end up with an inaccurate conversion.