Lux to Foot Candles Converter
Convert between lux (metric) and foot-candles (imperial) illuminance units
How to Use This Calculator
Select Conversion Direction
Choose whether you want to convert from lux to foot-candles or from foot-candles to lux.
Enter Illuminance Value
Input the illuminance value in the unit you're converting from (lux or foot-candles). For example, 500 lux for typical office lighting, or 50 foot-candles.
Convert
Click the "Convert" button to get the illuminance value in the other unit.
Conversion Formula
1 lux = 0.092903 foot-candles
1 foot-candle = 10.764 lux
Conversion Formulas:
- Foot-Candles = Lux × 0.092903
- Lux = Foot-Candles × 10.764
Why this conversion factor?
The conversion factor comes from the relationship between square meters and square feet: 1 m² = 10.764 ft². Since both lux and foot-candles measure illuminance (luminous flux per unit area), the conversion factor is the inverse of the area conversion.
Example Calculations:
Lux to Foot-Candles:
500 lux × 0.092903 = 46.45 foot-candles
Foot-Candles to Lux:
50 foot-candles × 10.764 = 538.2 lux
About Lux to Foot Candles Converter
Lux and foot-candles are both units of illuminance (luminous flux per unit area), measuring how much light falls on a surface. Lux is the metric unit (lumens per square meter), while foot-candles is the imperial unit (lumens per square foot). This converter helps you convert between these units, which is essential when working with lighting specifications, standards, or equipment that use different measurement systems.
When to Use This Calculator
- Lighting Design: Convert between metric and imperial lighting specifications
- Standards Compliance: Work with lighting standards that use different units
- Equipment Selection: Compare lighting specifications from different manufacturers
- International Projects: Convert between measurement systems for global projects
- Educational Purposes: Understand the relationship between metric and imperial units
Why Use Our Calculator?
- ✅ Bidirectional Conversion: Convert from lux to foot-candles or vice versa
- ✅ Instant Results: Get accurate conversions immediately
- ✅ Easy to Use: Simple interface with clear input fields
- ✅ Accurate: Uses precise conversion factors
- ✅ 100% Free: No registration required
Common Applications
Building Codes: Building codes and lighting standards often specify illuminance requirements in different units. In the US, foot-candles are commonly used, while many other countries use lux. This converter helps architects and engineers work with both systems.
Lighting Equipment: Lighting manufacturers may specify products in different units depending on their market. This converter helps compare specifications and select appropriate lighting for projects.
Photography and Videography: Photographers and videographers may encounter light meters that use either unit. This converter helps interpret measurements and ensure proper exposure settings.
Tips for Best Results
- Remember that foot-candles are approximately 1/10th of lux (more precisely, 1 fc ≈ 10.764 lux)
- For quick mental conversion: 1 lux ≈ 0.1 foot-candles, 1 foot-candle ≈ 10 lux
- Both units measure the same physical quantity (illuminance), just with different area units
- Typical values: Office lighting ≈ 300-500 lux (30-50 fc), Reading ≈ 500 lux (50 fc)
- Outdoor daylight can be 10,000-100,000 lux (1,000-10,000 fc)
- The conversion factor is exact based on the relationship between square meters and square feet
Frequently Asked Questions
What is the difference between lux and foot-candles?
Lux and foot-candles both measure illuminance (light per unit area), but use different area units. Lux uses square meters (lm/m²), while foot-candles uses square feet (lm/ft²). One foot-candle equals 10.764 lux, since 1 square meter equals 10.764 square feet.
Which unit is more commonly used?
Lux is more commonly used internationally and is the SI unit. Foot-candles are more commonly used in the United States, especially in building codes and lighting standards. However, the trend is moving toward using lux globally.
Is the conversion factor exact?
Yes, the conversion is exact: 1 foot-candle = 10.764 lux (more precisely 10.7639104...). This comes from the exact relationship: 1 square meter = 10.7639104167 square feet. The calculator uses the precise conversion factor.
What are typical illuminance values in both units?
Typical office lighting: 300-500 lux (30-50 fc). Reading: 500 lux (50 fc). General indoor: 200-500 lux (20-50 fc). Bright outdoor daylight: 10,000-100,000 lux (1,000-10,000 fc). Overcast day: 1,000-10,000 lux (100-1,000 fc).
Why do we need both units?
Historical reasons and regional preferences. The US traditionally uses foot-candles, while most other countries use lux. However, both measure the same physical quantity and can be easily converted. Many modern standards are moving toward using lux exclusively.