Using color to add meaning only provides a visual indication, which will not be conveyed to users of assistive technologies – such as screen readers. Ensure that information denoted by the color is either obvious from the content itself (e.g. the visible text), or is included through alternative means, such as additional text hidden with the .visually-hidden class. 
Learn more about this component on bootstrap's official documentation
Badge scaling
 Badges scale to match the size of the immediate parent element by using relative font sizing and 
                                                em units Badge Scaling Examples
Example heading New
Example heading New
Example heading New
Example heading New
Example heading New
Example heading New
Badge in buttons
 Badges scale to match the size of the immediate parent element by using relative font sizing and 
                                                em units Regular buttons
Outline buttons
Icon badges
 Use utility classes with 
                                                
                                                
                                                
                                            .btn-icon to place the badge Status badges
 These badges are unique and triggered by wrapping an element with 
                                                .status class. Comes with three badge sizes .status-sm, .status-xs and the default .status. Comes in 3 colors, .status-danger, .status-warning, and .status-success
                                                Contextual variations
 Add any of the below mentioned modifier classes to change the appearance of a badge. 
                                                
                                                        Primary
                                                        Secondary
                                                        Success
                                                        Danger
                                                        Warning
                                                        Info
                                                        Light
                                                        Dark
                                                    
                                                 Border utility 
                                                
                                                        Primary
                                                        Secondary
                                                        Success
                                                        Danger
                                                        Warning
                                                        Info
                                                        Light
                                                        Dark
                                                    
                                                Pill badges
 Use the 
                                                .badge-pill modifier class to make badges more rounded (with a larger border-radius and additional horizontal padding). 
                                                        Primary
                                                        Secondary
                                                        Success
                                                        Danger
                                                        Warning
                                                        Info
                                                        Light
                                                        Dark
                                                    
                                                Links example
 Add 
                                                
                                            .badge-* class on a hyperlink element to convert it to actionable badges with hover and focus states Nested badge
 Use the included color utilities to change background and text colors. Below are examples of nested badge with different background colors 
                                                
                                                        
                                                            
                                                                
                                                                    
                                                                        
                                                                            Nested Badge 1
                                                                        
                                                                    
                                                                
                                                            
                                                        
                                                        
                                                            
                                                                
                                                                    
                                                                        
                                                                            Nested Badge 2
                                                                        
                                                                    
                                                                
                                                            
                                                        
                                                        
                                                            
                                                                
                                                                    
                                                                        
                                                                            99+
                                                                        
                                                                    
                                                                
                                                            
                                                        
                                                    
                                                Badge header
 We use 
                                                
                                                
                                            .badge-icon with a combination of other utility classes to create a link badge. This class will auto turncate overflow giving you a nice clean look without any hassle