Calculating your LED light strip power needs

How do I know which power supply to use with my lights?

Need to figure out which power supply you need?

This is where some math is going to be needed, but this math is even easier than figuring out the fifteen percent tip at restaurants, I promise! So let's say you've picked out a strip already. each strip also lists its power consumption in watts per foot. In our little hypothetical shopping scenario here, let's pick out the 2835 high density Luma5 EX strip, and you've decided that for your project you'll need twenty five feet of lights. The Luma5 EX high density LED light strip is listed at 2.4 watts per foot, so for 1 roll of light, you'll be drawing about sixty watts of power, and we've got the right wattage of power supplies!

That formula again : (Strips Wattage per Foot) x (Total Feet of Strip) = Total power output in (Watts)

Note: It will be good to to add a buffer of +20% to handle any possible power surge or fluctuations for safety.

What if I want to use a wall dimmer with my LED lights?

Well that's certainly possible, there are a few things you'll need to know. First off, you'll need to use a dimmable LED driver instead of a standard power adapter. Another thing to note is that using a wall dimmer and the dimmable LED driver will require you to hard wire the lights directly into the switch. That, or you'd need to wire your dimmer switch into a wall outlet and attach and AC power cable to your strips and dimmable LED driver and use that outlet. The last thing you'll need to know about wall dimmers and the dimmable LED driver is that RGB LED strip lights just don't have a good way to work with the wall dimmer. No cause for alarm though, as all of our RGB LED light strip controllers can dim our RGB LED Kit strip lights, so you'll still be able to dim your lights!

What if I want to use a battery pack for portable power?

Please do! Our LED light strips are great for any mobile project and can be powered up by battery packs as long as it can supply the right needed power, like Light Bikes or outdoor lighting that's not near any convenient power sources. So if you were planning a romantic picnic dinner in a field and candles aren't your thing? Then you should pick up a 12V rechargeable battery pack and a nice RGB LED light strip! 12V rechargeable battery packs are also great for boat lighting, assuming that the battery pack stays dry and your strips are rated for some to a lot of water! 

How can I know how long the battery pack will last with my lights?

The 12V rechargeable battery packs are rated in milli-amp hours, either 3800 or 6000 milli-amp hours. To determine how many amps your strips are drawing, you'll need to find their wattage, so let's use a really easy example. A regular density 2835 LED light strip draws twenty-four watts, now take the wattage and divide it by twelve, that's your amp draw, or two amps. Now multiple your amp draw by one thousand, that's your milli-amp draw, so for the 3500 mAh rechargeable battery pack and a 2835 regular density LED strip, your battery pack will last 3500/2000=1.75 hours, or 104 minutes. Here's the general formula: (watt draw) / 12=A, A x 1000=M, Battery Pack Milli-amps / M= hours of battery life. I hope this helps you plan your battery pack outings! You can also use this simple battery life calculator tool.

(Need a power supply or a low voltage dimmable driver? Check out our selection here)


Choosing the right power supply is all part of choosing the right products for your project. Even more important is choosing the right LED light strip.

Thanks for reading this installment of our troubleshooting series, we truly hope it has been helpful. Have a question we haven’t answered yet?

Please remember that our customer service staff is happy to assist you with any and all of your concerns, questions, and suggestions. If you want to call and talk with us, well that’s just fine too –  1 (855) 768-4135!

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