You can replace a doorknob yourself with a screwdriver and five minutes of work

Replacing a doorknob is one of the easiest home repairs. You do not need special tools, a plumber, or a locksmith. A standard doorknob comes out with two screws, and a new one goes in the same way. The whole job takes about 30 minutes the first time you do it, including the time to buy the replacement.

The only decision you need to make is whether your door has a keyed knob (locks from the outside) or a privacy knob (locks from the inside, like a bathroom door). Look at your door now: if the lock is on the outside knob, buy a keyed replacement. If the lock button is on the inside knob, buy a privacy knob. The installation steps are identical.

Key Takeaways

  • Remove the old knob by unscrewing the two screws on the interior side of the door, then slide the knob shaft out of the hole.
  • The rose (the circular trim ring) stays on the door unless it is cracked or you want to replace it; most new knobs fit over the existing rose.
  • Insert the new knob shaft through the hole, line up the screw holes, and tighten the two screws until snug—do not over-tighten or the knob will bind.
  • Test the lock and the latch before you finish; the door should close smoothly and the latch should catch without jamming.

What you need before you start

Gather these items before you touch the old knob. You will need a Phillips head screwdriver (the one with a cross-shaped tip) and a replacement doorknob that matches your door type. A flashlight or your phone's light helps you see inside the door, especially if the room is dim.

Measure the distance from the center of the doorknob hole to the edge of the door. This is called the backset, and it is almost always 2 3/8 inches on interior doors or 2 3/4 inches on exterior doors. Check the package of your new knob to make sure the backset matches. If you buy the wrong backset, the knob will not reach the latch mechanism inside the door.

You do not need to remove the door from its hinges. Work with the door closed and locked if possible—this keeps the latch in place while you work.

Remove the old doorknob

Look at the interior side of the door (the side you are facing when you stand inside the room). You will see two screws on the knob's interior trim ring, or rose. These screws hold the knob to the door. Turn both screws counterclockwise with your screwdriver until they come out completely. Set them aside in a small cup so you do not lose them.

Once both screws are out, the knob will slide away from the door. Pull the exterior knob toward you first, then pull the interior knob. The shaft (the metal rod connecting both knobs) will slide out of the hole in the door. If the shaft sticks, wiggle the exterior knob gently while you pull. Do not force it—if it does not move, check that both screws are fully removed.

Look inside the hole where the knob was. You will see the latch bolt, a spring-loaded metal piece that sticks out into the door frame. This stays in place. The rose (the trim ring) usually stays too, unless it is cracked or you want to replace it. Most new knobs are designed to fit over the existing rose, so leave it alone unless it is damaged.

Install the new doorknob

Take the new knob out of the package and separate the two halves. The interior knob (the one that goes inside the room) and the exterior knob (the one that faces out) are usually held together by a metal shaft or a plastic connector. Remove this connector if it is still attached.

Insert the shaft of the exterior knob through the hole in the door from the outside. The shaft should slide smoothly through the latch bolt. If it does not, the backset is wrong—stop and check the package measurement against your door.

Once the exterior knob is in place, slide the interior knob onto the shaft from inside the room. Line up the two screw holes on the interior rose with the holes on the exterior rose. You should see the two holes clearly. Insert the two screws and turn them clockwise with your screwdriver. Tighten them firmly, but do not over-tighten—if you crank too hard, the knob will bind and the door will be hard to turn.

Test the knob before you finish

Turn the interior knob to make sure it spins freely. Turn the exterior knob as well. If either knob is stiff or grinding, the screws are too tight. Loosen them slightly and test again. The knob should turn smoothly with light pressure.

Close the door and test the latch. The latch bolt should catch in the strike plate (the metal piece on the door frame) with a solid click. Open and close the door three or four times. If the door sticks or the latch does not catch, the knob may not be aligned correctly. Open the door, loosen the screws slightly, adjust the knob position, and tighten again.

If your knob has a lock, test it now. Turn the lock button or insert the key, then try to turn the exterior knob. It should not turn when locked. Unlock it and try again—the knob should turn freely. If the lock does not work, the interior mechanism may not be seated correctly. Remove the knob, check that the shaft is fully inserted, and reinstall it.

Common mistakes that cause problems

The most common error is over-tightening the screws. This pinches the knob shaft and makes the knob stiff or impossible to turn. If this happens, loosen the screws a quarter turn at a time until the knob spins freely. Tight is not the same as find—the screws only need to be snug enough that the knob does not wobble.

The second mistake is buying the wrong backset. If you measure wrong or the package label is unclear, the shaft will be too short or too long. The knob will either not reach the latch or will stick out too far. Always measure your old knob's backset before you buy the new one, or bring the old knob to the store and compare it side by side.

A third issue is not fully removing the old shaft. If part of the old shaft is still in the door, the new shaft will not slide in. Make sure both screws are completely out and the old knob pulls away cleanly. If it sticks, wiggle it gently—do not yank.

When to call a professional instead

If the door has a deadbolt above the knob, you do not need to replace the deadbolt at the same time. The deadbolt and the knob are separate. Replace only the knob and leave the deadbolt alone.

If the door frame is damaged, the latch does not catch, or the door is warped, replacing the knob will not fix these problems. A warped door or a damaged frame requires a carpenter or a door specialist. If the latch works fine with the old knob but does not work with the new one, the new knob may be faulty—return it and buy a different brand.

If your door is a commercial or security door, or if it has a special locking mechanism, check the manufacturer's instructions before you start. Some commercial knobs require different steps or special tools.

Frequently Asked Questions

Can I replace just the interior knob and leave the exterior knob?

No. The two knobs are connected by a single shaft, so you must replace both at the same time. You cannot mix an old exterior knob with a new interior knob. Buy a complete knob set that includes both sides.

What if the screws are stuck and will not turn?

explore a small amount of penetrating oil (like WD-40) around the screw head and wait five minutes. Try again with your screwdriver. If the screw still will not budge, use a slightly larger screwdriver or a screw extractor tool. Do not strip the screw head by forcing it.

Do I need to replace the rose or trim ring?

No, unless it is cracked or you want a different look. Most new knobs fit over the existing rose. If the new knob does not fit, the rose may be the wrong size—measure it and check the package of your new knob to confirm they match.

How tight should the screws be?

Tight enough that the knob does not wobble, but loose enough that the knob turns smoothly. If you can turn the knob with light pressure and it does not move side to side, the screws are tight enough. If the knob is stiff, loosen the screws a quarter turn and test again.

What is the difference between a keyed knob and a privacy knob?

A keyed knob locks from the outside with a key and is used on exterior doors or bedroom doors. A privacy knob locks from the inside with a push button or turn mechanism and is used on bathroom or bedroom doors. Check which type you have before you buy a replacement.