| Title | Test
                    Find
                    
                    Password | 
            
                | Expression | ^([a-zA-Z0-9]{6,18}?)$ | 
            
                | Description | My simple but effective password regex. The password can only contain letters and/or digits and must be at least 6 characters long and no more than 20. I know it says {6,18} but it just works out that way. The question mark was added for optimization. Also, the password can not begin or end with a space or underscore. | 
            
                | Matches | abc123 | 
            
                | Non-Matches | _abc123_ | 
            
                | Author | Rating:  tedcambron | 
            
                | Source |  | 
            
              | Your Rating |  | 
        
    
 
    
    
     
        
                
	                Title: Can't contain other characters
	                Name: Ted Cambron
	                Date: 9/20/2014 7:26:00 PM
	                Comment: 
This pattern does limit just to letters and digits. #12343& or $10000! would not pass
                
                
            
                
	                Title: You Are Wrong
	                Name: blah
	                Date: 6/6/2009 10:04:42 AM
	                Comment: 
aaaa will match, that seems like 4 characters to me.
                
                
            
                
	                Title: Thank You
	                Name: Ted Cambron
	                Date: 2/22/2008 8:31:31 PM
	                Comment: 
Thanks for the advice. I think?
                
                
            
                
	                Title: Can contain other characters
	                Name: Michael Ash
	                Date: 2/22/2008 1:25:27 PM
	                Comment: 
This pattern does not limit just to letters and digits.
#12343& or $10000! would pass