LED driver sizing

LED Watts to Amps Calculator

A = LED Watts ÷ Supply Voltage

LED Watts to Amps Calculator

Size LED power supplies and low-voltage wiring from total LED watts.

Live Result
Formula-backed — instant professional result
REQUIRED CURRENT
0 A
Also equals 0 mA
Formula used A = LED Watts ÷ Supply Voltage Choose a power supply with current headroom above the calculated draw. 60W ÷ 12V = 5A

This calculator is an educational planning estimate. Verify safety-critical work with equipment nameplate data, local electrical code, and a qualified professional.

Find LED current draw from wattage and voltage. Supports 12V, 24V, and 120V LED strips, bulbs, and drivers. Wire sizing included.

Low-voltage LED planning

LED driver load path

Find LED current draw from wattage and voltage. Supports 12V, 24V, and 120V LED strips, bulbs, and drivers. Wire sizing included.

12V DC formula-first page-specific visual

LED Watts to Amps Calculator — Driver & Strip Lighting | Ampstowatt Guide

LED driver path

Driver watts divided by low-voltage DC supply

LED loads are usually low-voltage DC, so the useful visual is a driver feeding a strip with current, voltage, and wire checks shown together.

Formula Amps = Watts / Volts
LED Watts to Amps Calculator — Driver & Strip Lighting | Ampstowatt technical circuit diagram A premium electrical diagram showing the main values and conversion flow for LED Watts to Amps Calculator — Driver & Strip Lighting | Ampstowatt. LED driver 12 V / 24 V A = W / V Strip load Voltage drop
LED Watts to Amps Calculator — Driver & Strip Lighting | Ampstowatt LED driver path with real formula values and planning checkpoints.

Quick answer

Use this calculator to size LED driver current and low-voltage wiring.

LED strips and lamps often run at 12V or 24V DC. The current result helps check driver capacity, wire gauge, voltage drop, and connector limits.

Amps = Watts / Volts

Inputs to check before calculating

  • Use the total LED wattage after adding all strips or fixtures.
  • Match the voltage to the driver output, usually 12V or 24V.
  • Leave driver headroom instead of running the supply at its full rating.
  • Check long strip runs for voltage drop and uneven brightness.

Example: 1,200 watts at 12 volts

At 12 volts, a 1,200 watt load draws 100 amps before AC power-factor adjustments. Use the power factor field when the equipment is a motor, compressor, inverter, or other inductive load.

Best use cases

  • LED strips and drivers
  • Low-voltage DC
  • Current draw output
  • DC load planning with clear unit labels.

Common mistake to avoid

Do not size a driver from one strip section if multiple strips are connected to the same supply.

How to use the result

Use the calculated amps to choose a driver, fuse, connector, and wire size with headroom.

Accuracy and safety note

Calculator output is a planning estimate. Final breaker sizing, wire gauge, derating, voltage-drop limits, equipment protection, and code compliance should be verified with manufacturer documentation and a qualified electrician or engineer.

For the broad formula, reference table, and breaker planning context, start with the main Amps to Watts Calculator.

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Methodology, Review Notes, and Sources

How this calculator works

The calculator applies Watt's law for DC and resistive loads, then adds power factor for AC loads and the 1.732 multiplier for balanced three-phase line-to-line calculations.

  • DC and resistive loads: W = A x V
  • Single-phase AC: W = A x V x PF
  • Three-phase AC: W = 1.732 x A x V x PF

Editorial review

Last reviewed: June 26, 2026. Ampstowatt.com is built around the amps to watts conversion — our core specialty. Content is maintained by the Ampstowatt editorial team and checked for formula consistency, unit labels, calculator behavior, and safety wording.

The page is an educational planning reference, not a licensed electrical design or inspection service.

Reference sources

FAQ

LED W to A FAQ

Fast answers before you use the calculator or compare formulas.

LED How do I calculate LED strip current draw?

Divide total LED strip wattage by the supply voltage: Amps = Watts ÷ Volts. A 5-meter strip rated at 14.4 watts per meter on 12V draws (14.4 × 5) ÷ 12 = 6 amps. Always total all connected strip lengths before sizing the driver.

DRV What size LED driver do I need?

Calculate total LED watts, then choose a driver rated 15–20% above. For 72W of LED strips, use an 85–90W driver. Running a driver at full capacity reduces its lifespan and can cause flickering. Also match the driver output voltage (constant voltage 12V or 24V) to the LED strip requirements.

DIM Why do long LED strips dim at the far end?

Voltage drop across the copper traces inside the strip reduces voltage at the far end, causing dimmer LEDs. At 12V, even a 0.5V drop is a 4% loss. Solutions: run power from both ends, use 24V strips instead of 12V, use heavier gauge feed wires, or add injection points every 5 meters.

VS 12V vs 24V LED strips — which should I use?

24V strips are better for long runs because the same wattage draws half the current, reducing voltage drop by 75%. A 72W installation at 12V draws 6A; at 24V, only 3A. Use 12V only for short runs under 3 meters or when compatibility with 12V automotive or battery systems is needed.

WIR How do I wire multiple LED strips to one driver?

Connect strips in parallel to a constant-voltage driver. Each strip draws its own current, and the driver must supply the total. Three 24W strips = 72W total → need a 72W+ driver. Use adequately sized wire from the driver to each strip branch, and ensure each run is fused appropriately.

FUSE What fuse size do I need for LED strip power?

Calculate the total current: Amps = Total watts ÷ Volts. Add 20% for fuse headroom. For 72W at 12V: 72 ÷ 12 = 6A → use a 7.5A or 8A fuse. The fuse protects the wiring, not the LEDs. Ensure the fuse rating matches the wire gauge ampacity.