LED Strip Power Supply Calculator: How Much Power Do I Need?

💡 LED Strip Power Supply Calculator

Calculate the exact wattage & amperage needed for your LED strip installation

Quick Presets
📏Strip Details
💡 Power Supply Results
📊LED Strip Power Draw Reference
1.5W
2835 60LED/m per ft
3.0W
5050 RGB per ft
4.9W
COB 480 per ft
2.9W
2835 120LED/m per ft
4.0W
5050 RGBW per ft
2.2W
WS2812B per ft
2.0W
2216 120LED/m per ft
3.6W
5050 Single Color/ft
📋LED Strip Specifications & Max Run Lengths
Strip Type Voltage W/ft W/m A/ft Max Run (12V) Max Run (24V)
2835 SMD 60 LED/m12V/24V1.54.80.12516 ft (5m)33 ft (10m)
2835 SMD 120 LED/m12V/24V2.99.60.2416 ft (5m)33 ft (10m)
5050 SMD RGB 60 LED/m12V/24V3.010.00.2516 ft (5m)33 ft (10m)
5050 SMD RGBW 60 LED/m12V/24V4.013.30.3316 ft (5m)33 ft (10m)
5050 Single Color12V/24V3.612.00.3016 ft (5m)33 ft (10m)
COB 480 LED/m12V/24V4.916.00.4110 ft (3m)20 ft (6m)
2216 SMD 120 LED/m12V/24V2.06.50.1716 ft (5m)33 ft (10m)
WS2812B Addressable5V2.27.20.4416 ft (5m)N/A
🔌Power Supply Sizing Guide
PSU Rating Max Load (80%) 12V — Max ft (2835 60) 12V — Max ft (5050 RGB) 24V — Max ft (2835 60)
30W24W16 ft8 ft16 ft
60W48W32 ft16 ft32 ft
100W80W53 ft26 ft53 ft
150W120W80 ft40 ft80 ft
200W160W106 ft53 ft106 ft
350W280W186 ft93 ft186 ft
600W480W320 ft160 ft320 ft
📉Voltage Drop by Wire Gauge & Run Length
Wire Gauge Max Current Voltage Drop at 16ft Voltage Drop at 33ft Recommendation
28 AWG0.5A0.9V1.8VVery short runs only
24 AWG2A0.4V0.8VLow-power strips <30W
22 AWG3A0.25V0.5VStandard strips up to 50W
20 AWG5A0.16V0.32VMedium runs 50–100W
18 AWG8A0.10V0.20VLong runs >100W
16 AWG13A0.06V0.12VHigh-power installations
🏠Common Project Power Requirements
Project Strip Length Strip Type Total Watts PSU Needed (20% buffer) Amps Required
Under-Cabinet Kitchen16 ft2835 60 LED/m24W30W PSU2A @ 12V
TV Backlight10 ft5050 RGB30W40W PSU2.5A @ 12V
Bedroom Cove33 ft2835 120 LED/m96W115W PSU4A @ 24V
Living Room Accent49 ft5050 RGBW196W235W PSU9.8A @ 24V
Garage Workshop82 ftCOB 480402W480W PSU20A @ 24V
Stair Lighting26 ft2216 120 LED/m52W63W PSU2.6A @ 24V
⚡ 20% Safety Buffer Rule: Always size your power supply at least 20% above the calculated load. Running a PSU at 100% capacity causes overheating, shortens lifespan, and can create a fire hazard. A 20% headroom ensures stable voltage and cool operation. For example, if your strips need 80W total, choose a 100W PSU minimum.
📏 Voltage Drop & Max Run Length: For 12V strips, keep each individual run under 16 ft (5m) to avoid noticeable dimming at the far end. For 24V strips you can run up to 33 ft (10m). For longer installations, power the strip from both ends or use 24V. Alternatively, use a higher AWG wire (lower number = thicker wire) to reduce resistance over distance.

LED strip lights work on a totally different principle compared to your usual tubes. They are powered by low voltage DC flow, so you need a Power Supply that receives the 120V or 240V AC from your wall outlet and converts it to the right DC voltage. Most LED strips are designed for 12V or 24V DC, that is the best level for their use.

An easy solution is to use a 12V plug adapter. Here you find many possible options for instance a 24-watt 12V source, that is UL-certified and takes care of the change from 110. 240V AC to stable 12V DC output. They work well for LED strips and other devices with low voltage.

How to Choose a Power Supply for LED Strips

Many of them also include protection against overheating and come with longer cables, which really simplifies the setup.

Here the spot about the power… It matters more than one hopes. Every LED Strip has its own power rating, and the Power Supply that you choose must cover that need.

A 12V source with 5 amps maximum fits in around 60 watts. The best method that I found is to add roughly around 20% extra room for safety. So if your strips use about 48 watts, a 60-watt source ends up being the wiser chioce.

Some Power Supply units go beyond simply changing voltage. Some models even read signals from a dimmer and adjust the brightness up or down. The IDLV-series does that great; it gives steady voltage with PWM dimming, that goes from 0 to 100%, ideal for strips.

On the other hand, non-dimmable sources work also well, especially when you combine single color or multicolor strips with a separate controller.

For wet or damp places, waterproof models are available. Mean Well offers IP65- and IP67-rated sources specially for such cases. In demanding setups, a 24V 350-watt Power Supply placed in a weather-resistant box can care for longer lines or several strips combined.

Voltage drop steals from you with longer strips. The cables in the strip itself lose voltage over distance, something that the specs commonly point out as maximum run length. Star wiring, that goes directly to the Power Supply, helps too settle that, keeping every branch under around 100 watts for safety.

Good seals and a reliable Power Supply stays good practice, even for just one strip.

In campers and tents, many folks connect 12V LED strips directly to the 12V DC system of the vehicle and totally skip the AC-to-DC converter. Like this the lights work without need of extra connections or starting of the generator. One thing to watch, the voltage can spike up to about 14V, when the alternator starts, which can wear LEDs more quickly.

A step-down converter keeps thatvoltage at 12V.

For small portable setups, lithium batteries or USB power can feed some strips without complex wiring. An AC wall adapter plugged directly in the outlet works also, if you want something fast and without issues.

LED Strip Power Supply Calculator: How Much Power Do I Need?

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