Most LED strip lights can be cut to length, which is one of the reasons they are so popular for under-cabinet lighting, shelves and TV backlights. The catch is that you can only cut in specific places. Cut anywhere else and the section around the cut will stop working.
Where to cut
Look closely at the strip. Every few centimeters you will see a short line across it, usually between two pairs of copper pads and often marked with a small scissors icon. That is the cut line. On a typical 12 V strip the segments contain three LEDs; on 24 V strips they are often six LEDs long. COB strips (the ones that look like a continuous line of light) have much shorter segments.
Cut straight through the middle of the line with sharp scissors so that each side keeps half of the copper pads. Those pads are what you will use to reconnect power.
Before you cut
- Unplug the power supply. Low-voltage strips are not dangerous to touch, but cutting a live strip can short the driver.
- Measure twice. A segment you cut off is gone unless you solder it back.
- Check the direction arrows on addressable (pixel) strips: data only flows one way, so the piece you keep must start at the end that goes to the controller.
Reconnecting the pieces
The leftover piece is not wasted. It can be powered on its own or joined to another run:
- Solderless clip connectors are the easiest option. Match the connector to the strip width (8 mm, 10 mm, 12 mm) and the number of pads (2 for single color, 4 for RGB, 5 or 6 for RGBW or tunable white).
- Soldering gives the most reliable joint, especially on strips that will be bent or moved.
- On waterproof strips, peel back or cut the silicone coating to reach the pads, then reseal the end with an end cap and neutral-cure silicone if the strip will be used outdoors or near water.
LED lights you should not cut
Mains-voltage LED rope lights (120 V in the US) can sometimes be cut at marked points, but they need the manufacturer’s own connectors and end caps because the exposed conductors carry household voltage. If there is no clear cut mark or instructions, do not cut them. Fairy lights, LED bulbs, tubes and integrated fixtures are not designed to be cut at all.
If the strip stops working after cutting
Check that you cut on the line, that the connector pins actually sit on the copper pads, and that polarity matches (+ to +). The power supply should also match the new, shorter length: a shorter strip draws less power, which is fine, but a longer one joined from several pieces may need a bigger driver.
For more lighting choices around the house, see how to choose the right lighting for your home and the different types of light bulbs.
