Get the perfect fit: How to measure your door for a Bold smart lock?
Before ordering your Bold smart lock, it is essential to confirm your door's measurements. Bold smart locks come in standardised sizes (with adjustable components), so measuring correctly helps you select the right fit.
Use the sizing configurator below, or follow our step-by-step instructions to get the perfect fit.

Step-by-step measuring guide
First, make sure your door has an Euro Profile Cylinder.

To get started, you will need a measuring tape or a ruler.
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Find the centre screw hole of your current lock, this is your reference point.
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Measure from the centre screw hole to the outer edge of your door including any metal plating.(on the interior side).
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Repeat the process on the exterior side: from the centre screw hole to the outer door edge.
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Be sure to include any existing hardware or security features like core pull protection in your measurement. These may impact the total lock length required.


Adjustable outer length
Bold Smart Locks feature an adjustable outside module to accommodate different door thicknesses.
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Standard outside lengths: 30 mm or 50 mm
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Extension options: +5 mm, +10 mm, or +15 mm
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Example: The SX33 version can extend from 30 mm to 35, 40, or 45 mm using the included adapters.
Key considerations
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Mind the margin: Ensure at least 30 mm of space between the lock’s centre hole and the door frame on the inside. This prevents the thicker inside knob (47 mm wide and 39.5 mm deep) from being blocked or pinched.
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Sliding doors: The depth of the inside knob may limit movement. If your door slides open internally, double-check that this 39.5 mm depth allows for smooth operation.

Understanding the Bold Smart Lock’s dimensions
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Outside knob diameter: 32 mm
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Outside knob depth: 32.6 mm
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Inside knob diameter: 47 mm
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Inside knob depth: 39.5 mm
This means: The inside knob is thicker and extends further than the outside knob. Make sure your door has enough clearance, especially on the interior side.
By following these steps, you'll ensure that your Bold smart lock fits perfectly, providing both security and ease of use.