Installation Check
Answer 7 brief questions to find out if Nuki Smart Lock can be installed on your door lock.
nuki.io/checkInstallation requirements
Euro Profile Double Cylinder
with emergency function
Swiss Round Cylinder
with emergency function
Door fitting
shield or rosette fitting
Knob or handle
Nuki can pull the latch
Multipoint lock
Nuki can work with that
Horizontal key channel
no problem for Nuki
UK Oval Cylinder
with emergency function
American Dead Bolt
does not work
Additional security lock
does not work
Automatically locking lock
does not work
Euro Profile Double Cylinder (with emergency function)
We recommend using Nuki Smart Lock only with cylinders which have an emergency function. This function ensures that the cylinder can be used with a key on one side, when another key is inserted on the other side. Different suppliers of cylinders name this function differently, so e.g. it’s called “emergency function” or “external key override function”. Note that your key should rotate at the inside when you lock from the outside.
Usually, the exchange of your existing cylinder is not necessary, as most doors are already fitted with Euro Profile Double Cylinders. Nuki Smart Lock is mounted on the inside of your door on your existing Europrofile Double Cylinder. There is no need to make any changes on your door and therefore, you can still use your existing physical keys.
If you use a Nuki Smart Lock on a cylinder without emergency function, you can not lock the door with your mechanical key from the outside. Most locks can be simply extended with an emergency function. You can get more information about that from your local locksmith.
Indoor use only
The Smart Lock is designed for indoor use only. The operating temperature of the Smart Lock is in the range of 10–40°C. You must not mount a Smart Lock outdoors (e.g. at the garden gate), since it is not weather-resistant and can be removed.
Door fitting: Handle or knob
Nuki Smart Lock can pull the latch and is therefore suitable for doors with handle as well as for doors with knob on the outside. In the Nuki app you can configure whether Nuki should only unlock your door or even pull the latch to open the door for you.
Select your existing door fitting during the initial setup of your Smart Lock. To change the settings for your door fitting later, tap on the desired Smart Lock in the Nuki app and enter the lock settings. Then go to “Manage Smart Lock”. Here you can find the option “Choose door fitting” to change the setting.
Locking cylinder for door locks
A locking cylinder is that part of the door lock where you insert your mechanical key. This cylinder checks whether your key is authorized to lock the door.

The animation shows how a key is inserted into the locking cylinder. The reliefs of the key can set the pins in motion. Only a key with the correct reliefs brings the pins into the position that allows them to turn and thus lock.
Nuki changes neither the design nor the type of locking cylinder – Nuki is simply mounted on the inside of the door on the locking cylinder. In this way, we ensure that the security class and insurance cover of the door lock/door remain unchanged.

Depending on how far the locking cylinder is above the door fitting, Nuki is glued to the fitting or clamped to the cylinder.
Euro Profile Double Cylinder/Double Cylinder
A double cylinder or profile cylinder is a widely used locking cylinder form which is installed in door locks. Double cylinder means that this locking cylinder can be operated from two sides. So you can lock your door from the outside and the inside. Half cylinders, on the other hand, can only be locked from one side and are used, for example, for wardrobes or the like.
A double cylinder or profile cylinder is a widely used locking cylinder form which is installed in door locks. Double cylinder means that this locking cylinder can be operated from two sides. So you can lock your door from the outside and the inside. Half cylinders, on the other hand, can only be locked from one side and are used, for example, for wardrobes or the like.
Profile cylinders are standardised and can be replaced at any time. If you have a door lock that does not currently meet Nuki's requirements, your cylinder can be replaced.
Swiss Round Profile Cylinder/Round Double Cylinder
Round double cylinders or Swiss round profile cylinders do not differ from the Euro profile cylinders in how the door lock itself works and the locking feature. The difference lies in the profile shape.
This locking cylinder is very common in Switzerland and is also supported by Nuki. You can select the version that suits you on the product detail page.
UK Oval Cylinder
The UK Oval Cylinder is used in England and is, unfortunately, not supported due to its design. As with the Swiss round profile cylinder, the profile shape is the decisive factor. The mechanism of the locking cylinder is no different from that of the Euro Profile cylinder.
Knob cylinder
Knob cylinders are those locks/locking cylinders that can be operated from the outside using the mechanical key. Inside, however, these door locks have a knob used instead of a key. Nuki is compatible with knob cylinders of popular manufacturers.
Doorknobs are supported by Nuki.
What is the emergency function & how do I know that my cylinder is equipped with the emergency function?
The emergency function means that you can lock your door lock from the outside, even if there is a key inside the lock.
You can use Nuki without the emergency function (or priority function), but we strictly advise against it. You can have the emergency function for your existing door lock retrofitted. Contact your trusted locksmith for more information.
How do I know that my locking cylinder has an emergency function?
- Slide in a key one side and set at an angle
- Insert a key on the other side and try to lock it
- Is it possible to lock it?
- Yes → Your locking cylinder has the emergency function
- No → Your locking cylinder has no emergency function
Retrofit emergency function
If you don't want to change your keys, you can retrofit your door lock with the emergency function. This retrofitting is possible with locking cylinders from major manufacturers such as EVVA. You can find out whether your locking cylinder can be retrofitted from your trusted locksmith.
Cost: about €20-50
Advantage: existing keys can still be used.
Types of locks supported under certain conditions
Self-locking panic switch lock
The self-locking panic switch lock is a type of lock that automatically locks the door lock as soon as the door is closed. When the lock is opened, not only the latch and the bolt are pulled, but also an internal self-locking mechanism. As soon as the door is closed, the locking bolt is pushed forward by actuating a control latch, thus locking the door.
When the lever handle is pressed, the bolt and latch are retracted and the lock is unlocked. This type of lock is often referred to as an anti-panic lock.
Due to the door locking automatically, Nuki does not recognize the locking status of the door lock. But you can use Nuki to unlock it.
Door types and characteristics
Doors come in different designs. We are not aware of any problems with smooth doors. If there are reliefs, windows, patterns, etc. on your door, it is important that there is no elevation higher than the height of the door fitting within 30 mm of the lock. Otherwise Nuki cannot be fitted.

Another important factor is the backset. The backset refers to the distance from the centre of the keyhole to the outer edge of the door.
If a door opens outward, this distance must be significantly higher than 30 mm so that the door can be opened even after the Smart Lock has been installed.
Does my key fit Nuki?

A key is used to open a door. Nuki is supposed to revolutionize this key and thus enable keyless door opening. For Nuki to be compatible with the key, the following conditions must apply:
The key must not be thicker than 4 mm.

The bow is the part of the key which the person opening the door grasps. This part is also known as the key head. The following part of the key up to the reliefs is called the neck. The length of the bow including the neck must be less than 37 mm for Nuki to be compatible.
If a plastic cap is attached to the key, making the key thicker than 4 mm overall, it must be removed. This cap increases the thickness of the key, making the bow no longer fit into the Nuki.
The shape of the key head does not matter at all. It may be round, angular or oval.