How to Rekey a Door Lock
Whether you just bought a new home and want to replace the locks or are looking to reduce some clutter on your key-chain by matching all your locks to a single key, knowing how to rekey a lock yourself is a handy skill to have.
Without this knowledge, you are pretty much stuck buying those bulk cases of similarly keyed locks (which are typically pretty junky locks) or utilizing a locksmith to rekey your locks.
But if you want to take the path less traveled and rekey your locks yourself, this guide will hold your hand every step of the way and will work with a variety of cylinder locks, including Schlage, Kwikset, Baldwin, Yale, Corbin Russwin, and others!
Rekeying locks is pretty easy; however, expect to spend about 10 to 15 minutes per lock and about $30 to $50 for a rekey kit.
With that, let's get to it!
How Rekeying a Lock Works
The majority of locks found on doorknobs and deadbolts are pin tumbler locks. These types of locks utilize a series of pins called key pins (top pins) and driver pins (bottom pins).
Driver pins are the topmost pins and are all the same length. Their responsibility is to hold the lock shut when the correct key is not present.
However, the key pins are a variety of lengths and can be thought of as the combination of the lock. This combination is called the lock's bitting.
When the correct key with the correct cuts is inserted into the lock, the key pins will rise to the same level and push the driver pins out of the lock's core, allowing it to rotate and for the lock to open. To solidify this concept, check out the animation of a key entering a lock below.
Now, this is a mile-high description of how these locks work and if you would like to learn more, check out my guide on how the pin tumbler lock works. However, for the purpose of rekeying, this is all you really need to know.
To rekey a lock, all we need to do is swap out the bottom pins (key pins) with those that match the cuts of a different key—essentially changing the bitting of the lock to match the cuts of your new key.
Otherwise said, rekeying is nothing more than changing the combination of your lock.
Additionally, these different length key pins are standardized by manufacturers with a specific coding representing length. For example, Schlage locks have bottom pins coded between 0 and 9, 0 being the shortest at 0.165" and 9 being the longest at 0.300".
Different lock manufacturers have different pinning standards for their locks, which is why it's crucial to get the correct rekeying kit for your specific lock. We'll talk more about this in a moment!
Determine What Locks You Want to Rekey
Before you can begin rekeying your locks, you first need to identify which locks you want to repin and if they are compatible with the same key.
Sadly rekeying locks isn't as simple as matching any lock to a single key.
Different makes and models of locks use different keyways and keys. For example, a Kwikset key will not fit into the keyway of a Schlage lock.
Additionally, different lock manufacturers use various sized pins (length and width) and have diverse key bitting specifications.
To illustrate this, look at the difference between the heights of Schlage key pins vs. Kwikset key pins.
So if you have Schlage on your front door and a Kwikset on your garage door, you will either have to replace one of the locks with a matching brand or continue to use two different keys.
However, even when using the same brand for all your locks, you'll also want to verify that the locks use similar keyways.
This can easily be tested by fully inserting your desired key into all the locks. If the key goes in, it matches the keyway, and that lock can be rekeyed to that specific key.
Note that the key doesn't have to open the lock, just fit into the keyway.
Now that we understand exactly what locks we want to rekey let's look at the tools and equipment required!
Alright, so let's jump into the tools and equipment you will need to begin rekeying your own locks!
- Rekeying kit
- Plug follower
Let's jump into a few of these in more detail.
First, and most importantly, you will need a rekey kit for your specific lock brand. These kits contain each size bottom pin and will allow you to rekey a good number of locks!
I highly recommend the following kits for Kwikset, and Schlage locks as they are half the price of other hard case sets and come with two additional tools, a key gauge and plug follower—both of which will make your life easier!
Lock components are small and extremely difficult to replace using your fingers.
While regular household tweezers will work just fine, pinning tweezers are explicitly made for keying locks and have a gap that allows them to fit snugly around pins and grasp them firmly.
Continually dropping pins is a frustrating experience, so if you have a lot of locks to rekey, I would highly recommend picking some up. My go-to are Peterson's pinning tweezers.
A plug follower is used to push the plug out of the lock while at the same time holding the springs and driver pins in the upper lock cylinder. They are an invaluable tool to have, and repinning locks without them is no easy task—so I highly recommend picking some up!
If you buy one of the rekeying sets I've recommended above, they come with a follower. However, if you got with another rekey set, HPC has a nice set here.
Alternatively, you can use a ratchet socket of the correct size.
How to Determine Your Lock's Bitting
The first step in repinning your lock is to determine its bitting.
This can be accomplished in various ways, but we'll cover the two common and easy methods here.
Method 1: Use a Key Gauge
A key gauge is a quick and easy way to determine the bitting of your lock by measuring the depth of cuts on your key. They cost about $15, and you'll need to buy one that measures your particular lock's brand. So if you are rekeying a Schlage, you'll need a key gauge that measures a Schlage.
To use a key gauge, insert your key into the slot, and starting with the first cut on your key, slide your key down the gauge until it stops. The number that your key stops on is that cut's pin size!
For example, in the image below, I found that the first cut of my key was 3 and then used my gauge to determine my Schlage key had a bitting of 3-4-2-6-2.
Now by knowing your bitting code, you can quickly replace pins in your new locks without any guesswork, and if you ever lose your key, you can easily get a new one made from this code!
If you are interested in a key gauge and are keying a Schlage, Kwikset, Weiser, or Weslock lock, I highly recommend the Pro Lock KD01. If you have another lock brand, you can typically find a wide variety of gauges here.
Method 2: Use the Key as a Guide
If you don't want to splurge for a key gauge, you can also use the key that you wish to repin your lock to as a guide.
When you replace the pins into the lock, you can insert the key to verify their heights. If the pins are flush with the plug—like in the image below— they match the cuts of the key and are the correct size.
However, if the pins extrude from the pin chamber, they are too big, and if they don't quite reach the top, they are too small.
It's good practice to check your pin heights when installing new pins anyways, and we'll cover this in more detail in the steps below.
How to Rekey a Lock
Alright, with all the prerequisite information out of the way, let's jump into the steps of rekeying a doorknob lock.
To remove the lock cylinder from the lock, you will need the original key of the lock you desire to rekey.
If you have lost the original key, you'll either need to get a new one made or replace the lock entirely.
Step 1: Remove the Knob
The first step is to remove the knob and lock cylinder from the doorknob assembly. If you are rekeying a lock already installed on a door, you can rekey it without removing the entire assembly from the door.
Start by inserting your original key into the lock and turning the key 90 degrees towards the slot on the doorknob (as illustrated above). On some locks, this slot is a hole, while on others it is a slit cut with an exposed metal clip.
Using a screwdriver, paperclip, or another pointy object, press in on the clip and pull the knob off the door.
If the clip does not depress, the key has not been rotated to the correct position. Try turning it in the other direction.
Step 2: Remove the Lock Cylinder from the Knob
Next, we need to remove the lock cylinder from the handle.
Begin by rotating the key 90 degrees in the opposite direction that you did in step one, and then remove the key from the cylinder. If you're having issues removing the key, make sure that the key is vertical to the slot that we compressed in step 1.
Once the key is removed, remove the lock cylinder from the handle.
Some locks have a spring-loaded chamber (like in the image above) that needs to be compressed with a small flathead screwdriver in order to take it out of the handle.
Step 3: Remove the Cylinder Retaining Clip
Once you have your lock cylinder removed from the handle, flip it around and remove the retaining clip from the back.
Most locks will use a C-clip which can easily be removed using a clip removal tool. However, a screwdriver and a little elbow grease will work too.
Step 4: Remove the Plug from the Cylinder
Now it's time to remove the plug, which contains our key pins!
To remove the plug from the cylinder, insert the old key and rotate it 45 degrees left or right.
Using a plug follower—or alternatively, a ratchet socket that fits snug in the plug—push the plug out of the cylinder, ensuring that it stays tight against the plug the entire way out. Also, be sure not to rotate your plug and dump your key pins all over the floor.
Take things slow and don't force anything during this step as any mishaps could cause pins to drop out of the cylinder.
Once the plug has been removed, DO NOT remove the follower from the cylinder. At the current moment, it is keeping the top pins and springs within their chambers. If you do remove it, pins and springs will fall out and make your job a little more challenging.
If things do go wrong during this step and pins or springs do fall out, it's not the end of the world. Compress your springs and top pins back into their chambers and insert your plug follower to keep them in place.
Step 5: Remove Old Pins from Plug
Once the plug has been entirely removed, you can dump the old pins out of their chambers and remove the original key.
Step 6: Insert New Pins into the Plug
It's finally time to update those old pins with new ones.
- Pinning kit
- The new key you want to repin the lock to
- (Optional) The bitting code of your new key from a key gauge
You don't need the bitting code, but it does make things a lot easier as you know exactly what sized pins to put into each chamber. In my previous example, I determined my key bitting was 3-4-2-6-2. The first pin is the slot closest to the head of the key, while the last pin is the furthest.
In the example image above, I put the following sized pins in each pin chamber from left to right.
If you don't have a key gauge and don't know what pin sizes to use, here is a simple trick!
Insert the key that you want to reprogram the lock to. Begin inserting random pins into each slot and test their heights.
If the pin sits flush with the top of the plug (like in the illustration above), they are the correct size for that key.
However, if the pins extrude from the plug chamber, they are too long. Conversely, if the pins don't reach the top of the pin chamber, they are too short.
Step 7: Reassemble the Lock
Once you've replaced all the pins and have verified using the key that they are the correct heights, it is time to reassemble the lock!
With the key still in the lock, begin by reinserting the plug back into the cylinder and use it to slowly push the plug follower out of the cylinder.
Once the plug is in the cylinder, verify that the key turns smoothly, put the retaining ring back on, and remove the key.
Insert the lock cylinder back into the knob and then reinsert the key. Turn the key towards the push slot and then slide the knob back onto the rest of the assembly.
That's it! Your doorknob has been rekeyed! For any additional doorknobs, repeat the above steps.
How to Rekey a Deadbolt
If you need to rekey your deadbolt to match your doorknob, you can quickly rekey it in about 5 minutes!
To rekey a deadbolt, begin by removing it from the door, then separate the lock cylinder from the rest of the deadbolt.
Once the lock cylinder is out, you can rekey it just like you would a doorknob. Click here to jump up to those steps.
Note there is one significant difference between a deadbolt and a doorknob. While doorknobs typically use retaining clips, such as C-clips, deadbolts typically use retaining caps. Let's quickly look at how to take those off!
How to Remove a Retaining Cap
To remove the retaining cap, push in on the retaining pin with a small screwdriver and twist off the retaining cap. Try pushing it in from an angle to avoid the retaining cap from catching on your screwdriver.
Once detached, remove the retaining pin and its spring from the lock cylinder and put them in a safe place—don't forget this step!!
When to Change Your Door Locks Rather Than Rekey?
You have two options when you want to change your locks, rekey them or replace them. But which route should you take?
If you want to save some money, rekeying your locks is the way to go. However, there are a few situations where replacing them is a better option.
- If you want to rekey your locks to a single key, you'll need locks from the same manufacturer. For example, Schlage and Kwikset locks have different keyways and use different style keys. So if you have doors with locks from different brands, you'll need to pick a brand and replace the others.
- If you've lost your only key to a particular lock, you won't be able to rekey it. You're only options are to replace the lock, have a locksmith decode your lock and make you a new key, or decode the lock yourself!
- Replacing locks is also ideal if you don't want to deal with the hassle of rekeying your own locks or the cost of hiring a locksmith.
How Much Does a Locksmith Charge to Rekey a Lock?
In 2022 the average cost in the United States to hire a locksmith is $95. Additionally, the average price for a locksmith to rekey a lock is $20 and can run upward of $50 for more complex locks.
By that average, you would pay around $215 to have a locksmith rekey six locks. However, your cost could be more or less depending on where you live and who you hire.
If you want to save a lot of money, you can also bring your locks directly to a locksmith's shop. You won't have to pay the trip charge, and typically rekeys cost less in-house. But, this might not be a viable option if the locks are already installed.
At first glance, rekeying a lock may seem like a complicated and time-consuming task, but I hope this guide convinced you otherwise!
Learning how to rekey a lock yourself can save you money for years to come and only requires a small upfront cost for a rekeying kit that can be used on dozens of future locks.
If you liked this guide and would like to learn more about lock picking, home security, or locksmithing, be sure to check out my Academy for more free guides.