Download your Word document
Lumen and Illuminance Calculator result sheet — free, supported by sponsors. Your download button appears in 20 seconds.
This free download is supported by sponsors — continuing in
20
Your file is generated in your browser when you choose Download — nothing is uploaded. If this calculator returns enough numeric data, the export also includes its best-fit chart alongside the readable table.
WorldCalculate result export
Lumen and Illuminance Calculator — result sheet
Calculate luminous flux from candela and solid angle, then estimate illuminance in lux and foot-candles over an area.
Inputs used
Results
Visual chart
Breakdown
Calculation steps
Returned data table
Formula and methodology
Formula: Luminous flux Phi_v = I_v Omega; illuminance E_v = Phi_v/A.
The lumen is the photometric flux associated with luminous intensity over a solid angle. Dividing that flux by an entered area gives an ideal average illuminance, which is useful for unit checks but does not replace a lighting layout or measurement.
This result follows the calculator's declared inputs, precision, validation boundaries, and model limits.
Input contract
- Luminous intensity — cd; minimum 0; maximum 1000000000
- Solid angle — sr; minimum 0; maximum 12.566370614359
- Illuminated area — m²; minimum 1.0E-6; maximum 1000000000
Worked example
| Input | Value |
|---|---|
| Luminous intensity | 100 |
| Solid angle | 12.566370614359 |
| Illuminated area | 10 |
Luminous flux ≈ 1,256.64 lm; average illuminance ≈ 125.66 lux, or 11.67 foot-candles.
Assumptions and limits
- Candela, steradian, and area inputs follow photometric SI conventions.
- Intensity is treated as uniform across the entered solid angle and flux is spread uniformly over the entered area.
- Beam shape, distance falloff, reflector efficiency, spectral distribution, surface reflectance, and glare are not modeled.
Calculator note
Source and methodology
Use the official WorldCalculate methodology policy for the source, formula, precision, and boundary standards behind this calculator.
Planning estimate, not financial, medical, legal, or professional advice. © WorldCalculate — reuse with attribution. Built and curated by Hassan ALRowaie.
No saved result was found. Please run the calculation first, then choose Download again.