Lumens per square foot calculator

This calculator helps you determine the appropriate lumens per square foot needed for a space based on its dimensions and desired brightness level.

Input Parameters

Calculation Results

Calculation Formula

Total Lumens = Room Area × Desired Lumens per Square Foot

Where:
Room Area = Length × Width
Desired Lumens per Square Foot = The brightness level you want to achieve in the room

Lumens per square foot calculator Calculator Usage Guide

Learn how to use the Lumens per square foot calculator calculator and its working principles

How to use the calculator

  1. Enter the length of your room in feet.
  2. Enter the width of your room in feet.
  3. Specify the desired lumens per square foot based on your needs:
    • Very dim (close to candlelight): 5-10 lm/ft²
    • Dim (living room): 10-30 lm/ft²
    • Normal (office, bedroom): 30-50 lm/ft²
    • Bright (workshop, kitchen): 50-75 lm/ft²
    • Very bright (staging, outdoor): 75-100 lm/ft² or higher
  4. Click the "Calculate" button to determine the total lumens needed.
  5. Click "Reset" to clear all inputs and start over.

Understanding Lumens per Square Foot

Lumens per square foot is a measurement of room brightness. It tells you how many lumens of light are needed to illuminate a square foot of space. The higher the number, the brighter the room will be.

Example Calculation

For example, if you have a living room that is 12 feet long and 10 feet wide, and you want it to be bright (30 lm/ft²), your calculation would be:

Area = 12 ft × 10 ft = 120 sq ft

Total Lumens = 120 sq ft × 30 lm/ft² = 3,600 lumens

In this case, you would need a light fixture that produces approximately 3,600 lumens to achieve the desired brightness level in your living room.