What Is The Size Of A Doorknob Hole: Changing your current doorknob and fitting a new one is pretty straightforward. It is simply the case that you remove the old one and install another new and better one that will fit your door knob hole size perfectly.
The standard doorknob hole size for modern doors is 2 ⅛” in diameter. The size may be a little bit smaller for older doors. If you install an older door into a modern door knob, you may need to re-drill the knob hole for perfect installation.
Measuring the doorknob hole size is simple, too; just take the doorknob off, giving you great access to the hole, then measure its diameter. As simple as these tasks may be, you must be extra careful to drill the perfect hole to ensure easy fitting.
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What Is The Size Of A Doorknob Hole?
Door knobs are available in all shapes and sizes; you must know the hole size before fitting. The standard size for a door knob is two inches; however, the hole size of a deadbolt is always larger, sometimes two and a half inches.
What Size Is A Standard Doorknob Hole
The size of a standard doorknob hole is 2 ⅛ inches in diameter. This is the standard and most common size for most doors.
What Are The Measurements For A Doorknob
Selecting the right door now goes beyond appearance. To ensure a properly functioning door, you need to ensure that the door knob you choose is the accurate size for your door. The typical measurement for a door knob is either 2 3⁄8 inches or 2 3⁄4 inches. These knob sizes are for doors around 1 3/8 inches to 1 ¾ inches thick.
How Do I Know If A Doorknob Will Fit Into A Hole
Knowing the door knob hole size will guide you whenever you want to purchase the doorknob. Purchase the right doorknob for the whole, and you won’t have any issues fitting it.
How Do You Measure A Doorknob Hole -Step By Step
Measuring a door knob hole is relatively straightforward if you follow these simple steps;
- Take the doorknob off to get a clear look into the hole, then measure its diameter.
- Locate the widest point on the knob hole, mainly around the center.
- Get a measuring tape and place it on one of the ends for an accurate measurement.
- Most standard door knob holes are 2 ⅛ in diameter. If you got this exact measurement, It means you have a typical standard doorknob hole.
- If you got a smaller measurement, you have an old door that requires you to resize the doorknob hole.
- Measure the door thickness and the backset, and you are good to go.
Importance Of Door Thickness In Doorknob Placing
Measuring the thickness of your door before fitting the doorknob will prevent you from using special hardware to install the doorknob. If the door is standard, the doorknob will fit in perfectly. Although it may look simple, checking the thickness will save you from extra modification and frustration during installation.
Standard modern doors should be around 1 ¾ and 1 ⅜, and sometimes they may be as thick as two inches. Many door frames are designed to accommodate this thickness, and measuring it is simple.
Are Door Knob Sizes Universal
Most contemporary door knobs will be suitable for most standard doors. However, this is not a general rule or measurement. To be safer, measure the borehole, door thickness, and backset before fitting the doorknob. Note that the fit between the door and the knob solely depends on the door because older doors have smaller door knob sizes and modern doors.
Also, sometimes exterior doors have different door knob sizes compared to interior doors. You have access to several door knob designs, but the internal feature determines whether the door knob will be perfect for the door, not the exterior property.
Types Of Door Knob
There are different types and designs of door knobs, and whichever one you choose should be able to satisfy your door need.
- Passage Door Knobs
The highest percentage of doorknobs are passage door knobs. This means that they rarely lock but are primarily used to open and close a door. Also, these knobs are suitable for interior doors that do not mainly require a lock.
- Privacy Door Knobs
Privacy door knobs are the best for doors that require a lock, for instance, bedroom and bathroom doors. You can lock these door knobs from the inside by twisting the knob or through the keyed cylinder.
- Keyed Entrance Door Knobs
Keyed entrance door knobs are for exterior doors that need a lock. You can lock or unlock this knob by turning it or using a keyed cylinder.
- Dummy Door Knobs
Dummy door knobs are the best for doors that do not require a lock, such as a wardrobe or pantry doors. These door knobs are available in different styles and are primarily surface-mounted.
How To Install Doorknobs
Whether you fit a new doorknob to a new door or you want to replace an old knob, follow these steps;

- Place a latch plate suitable for your door mortise at the top of the latch.
- Fit the latch inside the edge of the door and ensure that the beveled side is not close to the jamb to make it easy for you to close the door.
- Use a hammer to position the latch correctly until it touches the end of the hole.
- Fit the latch into the door following the required structure.
- Fit in the first side of the doorknob via the latch, then join the second side of the know with the first side. At this stage, ensure that the two sides are aligned with their screw holes.
- Push both sides of the knob simultaneously and attach the two knob ends with screws.
- Get wood putty to put loose screws in place.
- Use a screwdriver to fit the strike plate, then check if the doorknob is working.
- If you have the time and resources, repaint the area close to the doorknob.
Conclusion
Installing a new doorknob to your door should be easy, provided you have the tools like a tape measure to get the right size of the hole. You can choose different types and styles of doorknobs, but the standard size of a doorknob hole that will fit most modern doors is 2 ⅛ inches.