The height of the door is used to determine how many butt hinges you need.
													
																	Standard size for door hinges. 
									
	
		
	
																	Commercial ball bearing hinges are typically for doors 1 5 8 1 3 4 thick. 
																	3 inches 3 1 2 inches 4 inches. 
																	Commercial spring hinges are typically for doors 2 2 1 4 thick. 
																	Door hinges are measured by the dimensions when the hinge is open and lying flat. 
															
													
									
	
		
	
																	They can come with both square and rounded corners. 
																	If it s a little wider than this up to 36 then bump that hinge height up to 4. 
																	For doors 1 3 8 thick and 32 in width the hinge height should be 3. 
																	For thicker doors around 1 and 36 wide the hinge will need to be 4. 
															
													
									
	
		
	
																	If wider up to 48 then scale up to a hinge height of 5. 
																	A 3 1 2 x 3 1 2 hinge will be 3 1 2 high have a center pin and two plates that are approximately 1 1 2 wide. 
																	Some larger residential doors usually entry doors use a 4 x 4 hinge. 
																	Most residential doors use a 3 1 2 x 3 1 2 hinges. 
															
													
									
	
		
	
																	In general you ll want to use one hinge for every 30 inches of door height. 
																	You may also find a few narrower doors in stock including 30 inches 28 inches and 24 inches. 
																	Standard interior door width is 32 inches. 
																	This is the minimum width required for a passage door. 
															
													
									
	
		
	
																	Use two hinges for doors up to 60 inches tall. 
																	With very few exceptions all standard door hinges are squares and sized in 1 2 increments ex. 
																	The common sizes for door residential door hinges are 3 and 3 1 2. 
																	Use three hinges if the door is between 60 and 90 inches tall.