Convert Lumen per Square Inch to Lumen per Square Foot

Convert lumens per square inch to lumens per square foot by entering a value below.

1 lm/in² (lumens per square inch) = 144 lm/ft² (lumens per square foot)

How to Convert Lumens per Square Inch to Lumens per Square Foot

The lumen per square inch and lumen per square foot are both units of illuminance. 1 lumen per square inch equals 144 lumens per square foot. This means to convert lumens per square inch to lumens per square foot, you multiply by 144.

Formula

lumens per square foot = lumens per square inch × 144

Step-by-Step Example

Convert 5 lm/in² to lumens per square foot:

1
Convert 5 lm/in² to lumens per square foot

We need to convert lumens per square inch to lumens per square foot

2
Apply the formula

Since 1 lm/in² = 144 lm/ft², multiply by 144

5 × 144 = 719.99999998

Answer

5 lm/in² = 719.99999998 lm/ft²

Lumen per Square Inch to Lumen per Square Foot Conversion Table

Quick reference table for common lumen per square inch to lumen per square foot conversions. Click any value for detailed calculation.

Lumens per Square Inch (lm/in²) Lumens per Square Foot (lm/ft²)
0.1 lm/in² 14.4 lm/ft²
0.5 lm/in² 71.999999998 lm/ft²
1 lm/in² 144 lm/ft²
2 lm/in² 287.99999999 lm/ft²
5 lm/in² 719.99999998 lm/ft²
10 lm/in² 1440 lm/ft²
25 lm/in² 3599.9999999 lm/ft²
50 lm/in² 7199.9999998 lm/ft²
100 lm/in² 14400 lm/ft²

About These Units

Lumen per Square Inch (lm/in²)

Lumens per square inch (lm/in²) equals 1,550 lux or 144 foot-candles. Used for high-intensity illumination of small areas: display lighting, inspection systems, and microscopy. One lm/in² = 144 lm/ft². Rarely used; lux or foot-candles preferred.

Lumen per Square Foot (lm/ft²)

Lumens per square foot (lm/ft²) is identical to foot-candles. The defining relationship: one foot-candle = one lumen per square foot. Used in US lighting calculations: lumens needed = foot-candles × square feet. Standard in American architectural lighting design.

Frequently Asked Questions

How do I convert lumens per square inch to lumens per square foot?

To convert lumens per square inch to lumens per square foot, multiply the value by 144. For example, 10 lm/in² = 1440 lm/ft².

How many lumens per square foot are in 1 lumen per square inch?

1 lumen per square inch equals 144 lumens per square foot.

What is the formula for lumens per square inch to lumens per square foot?

The formula is: lm/ft² = lm/in² × 144.