Hey there, if you’ve ever hung around the COB LED strip space, you’ve definitely run into 12V and 24V versions—they’re everywhere, from under-cabinet kitchen lights to custom accent strips for gaming setups. But let’s be real, when I first started out as a COB LED strip supplier, I just thought “higher voltage = brighter” and picked 12V for most small jobs. Spoiler: I messed up a few projects because I didn’t dig into the actual differences. That’s why I’m breaking this down like I would chat with a new client—no jargon, just real talk that’ll help you pick the right one for your next gig. COB LED Strip
First off, let’s keep the basics simple. Voltage for LED strips is basically how much electrical “push” is moving through the circuit. 12V is the old workhorse, the one most people are familiar with, like the power bricks you use for phone chargers or small desk lamps. 24V is the newer, beefier cousin, and it’s been blowing up over the last few years. But why does that matter for COB specifically? COB (Chip-On-Board) LED strips aren’t like old individual SMD strips with tiny little chips spaced apart—they have dozens of micro-LEDs crammed tight on a single circuit board, right next to each other. That tight packing means they run warmer, pull more current, and the voltage you pick hits way harder than it would for standard strips.
Let’s start with the big one: power loss over distance. This is probably the most important thing I see clients miss all the time. Let’s say you want to run a COB strip 10 feet from your power supply. For a 12V strip, the circuit board’s resistance means that by the time you get to the end of that 10 feet, you’ll lose about 15-20% of your voltage. What does that look like? The start of the strip is super bright, the end is dimmer, maybe even flickers a little, because there’s not enough push to feed the LEDs at the far end. Now 24V? That same 10 foot run only loses about 7-10% voltage. Double the voltage, half the power loss. That game changes when you’re running longer distances—like a 20 foot strip, or a 30 foot accent wall. I had a client last month who tried to use 12V for a 25 foot under-wall setup, and he ended up with a strip that was so dim at the far end he had to add two extra power supplies to fix it. He could’ve skipped that headache with a 24V strip.
Next up: current draw, which is directly tied to how big your power supply needs to be. Current is the amount of electricity pulling through the strip, measured in amps. Ohm’s Law (yeah, I had to dust that off from high school science) says power = voltage x current. So if a COB strip needs 10 watts of power to run correctly, 12V would need 0.83 amps (10 / 12 = ~0.83), while 24V only needs 0.42 amps (10 / 24 = ~0.42). That’s half the current! What does that mean in real life? Smaller power supplies, thinner wires, less heat from the wiring itself. For someone doing a quick under-cabinet install in a tiny kitchen, 12V might be fine, but if you’re doing a whole restaurant’s bar line, 24V strips mean you don’t have to hide big, clunky power supplies under every cabinet. I’ve standardized 24V for all my commercial clients now because it cuts their power supply costs by 30-40% just from smaller units.
Wait, but don’t sleep on the current downside, right? More current = easier to trip breakers if you’re not sizing up correctly. For a 24V strip, each power supply can handle way more total watts, so if you’re running a full room of strips, you need a bigger breaker? No, wait—let me clarify. If you have a 100 watt total load, 12V needs an 8.3 amp power supply, while 24V needs a 4.2 amp supply. That means for multi-strip setups, 24V uses smaller breakers, not bigger. The only time current is a problem is if you’re running tiny, short strips—like a 2 foot accent strip for a picture frame. 12V works here because the current is so low, it’s not an issue. But for longer runs, 24V wins hard.
Brightness and consistency—this is where COB really shines, because you don’t have those individual LED hotspots like on old strip lights. But voltage affects brightness too. Let’s compare two similar COB strips: one 12V, one 24V, both rated at 20W per meter. The 24V version will output a little more total light, around 5-10%, because it can deliver power more evenly along the strip without that end-of-run dimming. I tested this last month in my warehouse: I set up two 5 foot strips, one 12V, one 24V, same density of micro-LEDs, same power supply rating. The 24V strip was noticeably brighter across its entire length, while the 12V strip’s end was 18% dimmer, per my light meter. For residential use, that small brightness difference might not matter, but for commercial displays or outdoor signs, you need every lumen to be consistent.
Heat management is another big one, especially with COB strips since they run hotter. Less current means less heat generated in the wiring, but wait—does voltage affect the strip’s own heat? Let’s get real here: both strips produce roughly the same amount of heat for the same lumen output, because the total power is almost identical. The difference is where the heat goes. With a 12V strip, since it’s pulling more current, more heat is generated in the power supply and the wiring. With 24V, that heat is concentrated more on the strip itself, but wait—because you’re using thicker wires? No, thinner wires for same current. Wait, let’s correct that: if you use the correct wire gauge for each, 24V wiring runs 50% cooler than 12V for the same total load. That means less risk of wiring overheating, which is a big safety win. I’ve had clients with 12V installations in attics complain about warm wires—no one has that issue with 24V. Also, because the voltage drop is lower, the strip doesn’t have to work as hard to stay bright, so it doesn’t run as hot at the ends, extending the strip’s lifespan. I’ve seen 24V COB strips last 2-3 years longer than 12V ones in the same outdoor application, just from the lower operating temperature.
Now, what about the downsides? No tech is perfect. The first thing is that 24V systems aren’t compatible with 12V power supplies. So if you already have a bunch of 12V power bricks lying around, you can’t reuse them for 24V strips. That’s an extra upfront cost, especially if you’re swapping out an old setup. Also, for super small, short runs (under 3 feet), the voltage drop on 12V is so minimal that it’s not worth the extra cost of a 24V setup. For example, a 1 foot strip for a bookshelf edge? 12V is cheaper to source, works fine, no need to upgrade. Another thing: some older dimmers only work with 12V systems. But modern dimmers are catching up—most my clients use 0-10V dimmers that work with both, so that’s becoming less of a problem every month.
Wait, and let’s talk about outdoor use, because that’s where a lot of my clients go wrong. If you’re running COB strips on a patio, under a fence, or along a deck rail, 24V is basically the only way to go for runs longer than 5 feet. Rain, temperature swings, and the extra length of outdoor wiring make voltage drop way worse. I had a landscaper client last year who installed 12V strips along a 20 foot fence in Miami. After three months of heavy rain and heat, the far end of the strips stopped working entirely because the wiring corrosion added even more resistance, making the voltage drop so bad the LEDs couldn’t turn on. He swapped them for 24V strips and hasn’t had an issue in two years. That’s the kind of real-world test you don’t get from a spec sheet.
So when should you pick which one? Let’s break it down quick, no overcomplicating: go 12V if you’re doing short runs (under 3 feet), small DIY projects, or you already have 12V power supplies lying around. It’s cheaper upfront for tiny jobs, easier to source parts if you’re just messing around with a home gaming setup. Go 24V if you’re doing runs over 5 feet, commercial projects, outdoor installations, or any setup where you want consistent brightness across the entire strip. It’s worth the extra $10 or $20 for a power supply to avoid the headache of dim ends, extra power supplies, or early strip failure.
And for the record, as a COB LED strip supplier, I’m not shilling one over the other— I’ve got both in stock, because I know every project is different. Last week, a guy came in wanting 12V strips for his kitchen under-cabinet lights, which are only 2 feet long. Perfect, that’s his call. The week before, a café owner wanted 20 foot strips along their counter, and I sent him 24V, and he texted me that night saying how much brighter the whole counter looked, no weird dim spots. That’s what it’s about—matching the product to the job, not pushing the most expensive one just because it’s newer.
Wait, one more thing I should mention: dimming capabilities. Both 12V and 24V COB strips can be dimmed, but 24V dimmers tend to be more reliable for longer runs. I’ve had 12V dimmers flicker when paired with strips over 10 feet, but I haven’t seen that with 24V dimmers in years. If you want a smooth, flicker-free dim, especially for accent lighting in a bedroom or lounge, 24V is the way to go.
I think the biggest mistake people make is thinking 12V is always the cheaper option, but when you add up the cost of extra power supplies for long runs, or having to replace strips that died because they were running too hot, 24V ends up being more cost-effective long-term. For example, my 12V COB strips are $1.20 per foot, and my 24V are $1.50 per foot. But if you need two 12V power supplies for a 20 foot run, that’s $30 extra, plus installation time to hide two power supplies. The 24V setup uses one power supply for the same run, saving you that $30 and an hour of work. That math adds up fast.
Look, I’ve been in the LED strip game for 8 years, and I’ve seen every mistake a client can make. The difference between 12V and 24V COB strips isn’t just a number on a spec sheet—it’s about whether your end result is bright, consistent, and lasts for years, or if you’re troubleshooting dim ends and dead strips a month later. I don’t care if you buy from me or another supplier, just do yourself a favor and think about your run length and project size before pulling the trigger. If you’re not sure which one is right for your project, hit me up to chat—no hard sell, just someone who’s dealt with way too many bad installations and wants to help you get it right.
Now, if you’re ready to order or just have questions about which COB strip works best for your space, feel free to reach out. I’m happy to walk through your project, no pressure.
CCT Tunable White References
- LED University. (n.d.). Voltage Drop in LED Strips: Causes and Mitigation. Cree Lighting.
- Lighting Research Center. (2021). COB LED Strip Performance Metrics for Residential and Commercial Applications. Rensselaer Polytechnic Institute.
- National Electrical Code. (2022). Wire Gauge and Voltage Requirements for Low-Voltage Lighting Systems. NFPA.
- LEDinside. (2023). Global COB LED Strip Market: Voltage Segment Analysis. TrendForce.
Shenzhen Tingliang Optoelectronics Co., Ltd.
With over 15 years’ experience, we are one of the most professional cob led strip manufacturers in China. Please feel free to buy discount cob led strip for sale here and get quotation from our factory. We also accept customized orders.
Address: 2nd Floor, Building 1-6, Tongfuyu Industrial Zone, Shiyan, Bao’an District, Shenzhen
E-mail: tl@tl-led.cn
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