A standard tasting glass is about half the size of a regular serving, containing 2 to 3 ounces (75 to 90 ml) of wine. A bottle of wine contains approximately 10 servings, so for a group of 8 to 10 people, it is recommended to buy 2 bottles. The number of ounces in a bottle of wine is usually 25. Wineries typically serve 1- to 2-ounce samples of the wines being tasted, and a tasting flight can include up to six different wines. This means that each 1-ounce tasting sample would be equivalent to a 6-ounce one.
This amount is enough to take several sips of wine, analyze its characteristics and form a general opinion about it. A typical tasting wine will be around 2 ounces, while a typical wine flight will give you between 4 and 6 different wines to try, which would be equivalent to between 1.5 and 2.5 normal glasses of wine.