A typical bowl of cornflakes contains approximately 100–150 calories, depending on portion size and milk. A standard serving of dry cornflakes is about 1 cup (28–30 grams), which provides roughly 100–120 calories. When you add milk, the total increases: 1 cup of whole milk adds about 150 calories, while skim milk adds roughly 80–90 calories. So a complete bowl typically ranges from 180–270 calories total.
The exact calorie count varies by brand—some cornflake varieties contain slightly more or less cereal per cup due to density differences. Premium or frosted versions may have 120–130 calories per serving. To get a precise number, check the nutrition label on your specific box, which lists calories per serving and typical serving size in grams or cups.
If you're tracking calories, weighing your cereal on a kitchen scale provides the most accurate measurement. Most people naturally serve themselves 1 to 1.5 cups of cereal, putting a typical bowl in the 150–220 calorie range before milk, and 230–400 calories after adding milk of your choice.