Are you unsure whether a 5 m strip will light your entire cabinet or if you need a full 10 m run? This guide breaks down what those length labels mean, shows how power draw and voltage drop differ, and helps you choose the perfect strip length for any application.
The “5 m” or “10 m” label refers to the total length of LED strip on the reel or spool. A 5 m strip contains six 1 m segments of LEDs joined by soldered copper pads, while a 10 m strip doubles that length. You can cut at the marked cut-lines every 5 cm or meter, but you cannot extend beyond the rated length without power injection or risking voltage drop.
Is a 5 m LED strip enough for under-cabinet lighting? A standard 5 m strip will usually cover a single run under kitchen cabinets. If your run is longer, consider a 10 m strip or multiple shorter strips powered in parallel to maintain brightness.
LED strips typically draw 14.4 W per meter at 12 V (for 60 LEDs/m density). That translates to:
Length | Power per m | Total Power | Recommended PSU |
---|---|---|---|
5 m | 14.4 W/m | 72 W | 100 W 12 V supply |
10 m | 14.4 W/m | 144 W | 200 W 12 V supply |
How much power does a 10 m LED strip use?
A 10 m strip at 14.4 W/m draws approximately 144 W, so you’ll need at least a 200 W 12 V power supply to maintain safe headroom and prevent voltage sag.
As LED strip length increases, voltage drop becomes more pronounced, causing LEDs at the far end to appear dimmer. Voltage drop (∆V) is calculated as:
∆V = I × R × L
Worked example:
Graph showing voltage drop rising from 0.6 V at 5 m to 2.4 V at 10 m for a typical LED strip current.
To maintain even brightness on LED-strip runs exceeding 5 m, it’s essential to inject power at regular intervals and use appropriate wiring techniques:
How to power LED strips greater than 5 m?
Always inject 12 V power into the strip at least every 5 m using dedicated feed wires back to the PSU. If you can’t physically access midpoints, split the strip into parallel 5 m segments each powered directly to ensure stable voltage and brightness.
Choosing between a 5 m and 10 m LED strip hinges on your run length, power-injection access, and desired brightness consistency. Use a LED Voltage-Drop Calculator to verify voltage sag, and follow our LED Power-Injection Guide for wiring best practices. For technical standards, consult the DOE Solid-State Lighting Fact Sheet 2024 and the IEC Voltage-Drop Standard PDF.
Key takeaway: Match strip length to your layout and power-injection plan—5 m for short, single-feed runs; 10 m with multiple injection points or parallel segments for longer spans.