How many calories are in a 12 inch bun? The Ultimate Guide
                                
                                
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                                    7 min read                                
                            
                                The calorie count for a 12-inch bun can vary significantly, with one commercial white sub roll averaging around 408 calories while another brand's whole wheat version clocks in at 440. Knowing the nutritional impact of your bread is the first step toward making informed dietary choices for your sandwich.