There are more than a hundred different varieties of grapes existing in the world. These grapes come in a multiplicity of sizes- some as small as a quarter inch, some as large as 2 inches in diameter. In addition to being wide ranging in size, grapes also come in a range of colors such as green, yellow, red and purple. An accurate measure of grapes per serving will depend on several aspects. Firstly, one must consider the variety of grapes in question. Secondly, one must consider the person being served. All things considered, the experts consider 1 cup of grapes to be a proper serving. This amount would of course be reduced slightly for children. But how much is one cup of grapes exactly? The best guess is between 10 to 40 grapes per 1 cup, depending on the variety. A cup of tiny champagne grapes could be as many as 40, while only 10 larger concord grapes would fit in a cup. Regardless of the variety, grapes are a great source of vitamins and a great fruit for those who are watching their calorie intake. A cup of grapes has only about 100 calories and is free of harmful fats and sugars. In addition, it provides a gram of fiber and is very high in vitamins C and K.Grapes are very versatile; you can add them to vegetable salads, chicken salads and even tuna salads. They can be had for breakfast, lunch and dinner and everything in between! For long lasting storage, grapes can be frozen for up to 12 months in an airtight, freezer-safe container. Otherwise, grapes can be stored, unwashed, in the refrigerator for up to a week with no spoilage. Fun fact: Frozen grapes are a fun treat on a hot day.