Lumens to Watts Calculator

Find the right wattage for your lighting needs with our Lumens to Watts Calculator. Ideal for energy-efficient lighting planning.

Enter luminous flux in lumens:
Enter light source:
Or enter luminous efficacy in lumens per watt:
Power result in watts:

Whether you're a lighting enthusiast, homeowner, or professional in the lighting industry, this calculator is here to help. Let's explore how it works and why it's valuable.

How It Works: At the core of the Lumens to Watts Calculator is a straightforward equation:


Here's a breakdown:

Understanding this equation empowers you to determine the power your light source needs to produce a specific brightness. It's a key tool for informed decisions in selecting the right lighting solutions.

Watts to Lumens Calculator

Using the Calculator

  1. Enter Luminous Flux: Input the brightness of your light source in lumens.

  2. Luminous Efficacy: Specify the luminous efficacy, usually in lumens per watt (lm/W). The default is set at 100 lm/W, a common value for LEDs.

  3. Get Power: The calculator will display the required power in watts based on your inputs.

This process ensures you can accurately match the brightness you desire with the appropriate power consumption.

Conversion Chart

For quick reference, a conversion chart is provided, showing the wattage requirements for different levels of brightness for a light source with a specific luminous efficacy.

For example:

  • 5 lumens = 0.0555 W
  • 10 lumens = 0.111 W
  • 20 lumens = 0.222 W
  • 50 lumens = 0.555 W
  • 100 lumens = 1.111 W
  • 5000 lumens = 55.555 W

This chart simplifies the process of choosing the right bulb for your needs.

Exploring Efficiency

The Lumens to Watts Calculator is not just about brightness; it's also a tool to evaluate the efficiency of different lighting solutions. This is particularly useful when considering low-wattage LEDs, providing insights into potential electricity savings.