Light Tools
Calculators for illuminance, luminous flux, room lighting, LED efficacy, and photometry.
Lumens to Lux Calculator
Convert total luminous flux (Lumens) to illuminance (Lux = lm/m²) or Foot-Candles (fc = lm/ft²) with inverse square law distance calculations.
Candela to Lumens Calculator
Convert bidirectionally between luminous intensity (Candela) and total luminous flux (Lumens) using beam angle and solid angle steradians.
Illuminance Calculator (Lux & Foot-Candles)
Calculate illuminance from luminous flux or intensity using the inverse-square law, surface area, and incident angle theta.
Room Lighting & Lumen Calculator
Calculate required total lumens, foot-candles, and number of LED light fixtures for any room size using the Zonal Cavity Lumen Method.
LED Wattage to Lumens (Efficacy) Calculator
Convert bidirectionally between light output (Lumens) and electrical power (Watts) across LED, CFL, Halogen, and Incandescent lighting with annual cost savings.
Lighting Electricity & Operating Cost Calculator
Calculate daily, monthly, and annual lighting electricity costs, compare incandescent vs LED retrofit savings, and determine ROI payback period.
Color Temperature (Kelvin) & Mired Converter
Convert bidirectionally between Color Temperature in Kelvin (K) and Mireds (micro reciprocal degrees) with photographic filter shift calculations.
Light, Photometry & Lighting Design Calculators
Photometric and lighting calculations are essential for architectural lighting design, electrical energy audits, photography, horticulture, and workplace safety compliance. From determining required fixture counts for room blueprints to computing LED retrofit ROI and color temperature shifts, our precision tools handle all lighting conversions.
Our Flagship Lighting Tools Suite
Our comprehensive collection of lighting calculators applies rigorous IESNA, CIE, and SI photometric standards:
- Lumens to Lux Calculator: Convert total luminous flux to illuminance in Lux (lm/m²) or Foot-Candles (lm/ft²) across spherical and hemispherical distributions.
- Candela to Lumens Calculator: Bidirectional conversion between luminous intensity (Candela) and total luminous flux (Lumens) using beam angles and solid angle steradians.
- Illuminance Calculator: Compute surface illuminance using the inverse-square law, distance, and surface incident angle theta.
- Room Lighting & Lumen Calculator: Determine total lumens, foot-candles, and fixture layout counts for any room dimension using the Zonal Cavity (Lumen) Method.
- LED Wattage to Lumens (Efficacy) Calculator: Bidirectional conversion between light output and electrical power across LED, CFL, Halogen, and incandescent bulbs.
- Lighting Operating Cost & Electricity Calculator: Estimate daily, monthly, and annual electrical costs, compare incandescent vs. LED retrofits, and calculate payback periods.
- Color Temperature (Kelvin) & Mired Converter: Convert between Kelvin (K) and Mireds (micro reciprocal degrees) with photographic filter shift calculations (CTO/CTB).
All calculators feature real-time interactive tools, formulas, step-by-step mathematical proofs, and comprehensive educational guides.