Question 1

What is the difference between lumens and lux?

Accepted Answer

Lumens measure total light output from a source, while lux measures light intensity at a surface. Lux = lumens per square meter.

Question 2

How do I choose the right brightness for a room?

Accepted Answer

General lighting needs 300-500 lux, task lighting 500-1000 lux, and detailed work 1000+ lux. This calculator helps convert between lighting units.

Question 3

What is luminous efficacy?

Accepted Answer

Luminous efficacy (lumens per watt) measures how efficiently a light source converts power to visible light. LEDs typically achieve 80-120 lm/W.

Question 4

How do I convert between candela, lumens, and lux?

Accepted Answer

These units are related but measure different things. This converter handles the mathematical relationships, accounting for beam angle and distance where needed.

Lighting Power Density Light Converter - Free Online

Frequently Asked Questions

Explore Financial Toolset

Compound Interest Calculator

Mortgage Calculator

Debt Payoff Calculator

Retirement Calculator