A plain, medium-sized bagel typically contains about 270 to 300 calories. For example, a medium plain bagel weighing around 100 grams has approximately 264 to 271 calories

. Some sources note that bagels from bakeries, especially larger ones measuring around 6 inches, can have up to 350 calories or more

. Flavored bagels like chocolate chip or French toast varieties generally have higher calorie counts, sometimes exceeding 300 calories

. To summarize:

• Medium plain bagel (~100g): ~264–271 calories
• Larger bakery bagel (~6 inches): up to 350 calories
• Flavored bagels: often 300+ calories

Calories increase further if you add spreads or toppings like cream cheese or butter