Enter your garden lighting details
Example data table
| Scenario | Area | Target lux | Fixture lumens | UF | LLF | Margin | Fixtures | Spacing |
|---|---|---|---|---|---|---|---|---|
| Path edges | 12 m² | 25 | 300 | 0.60 | 0.80 | 10% | 2 | 2.2 m |
| Shrub bed accents | 20 m² | 80 | 450 | 0.55 | 0.75 | 10% | 5 | 1.5 m |
| Feature tree uplight | 10 m² | 120 | 600 | 0.50 | 0.70 | 15% | 5 | 1.0 m |
Examples are illustrative. Use your fixture specs and aiming plan.
Formula used
The calculator estimates total lumens needed for a target illuminance across an area:
Required Lumens = (Area × Target Lux) ÷ (UF × LLF) × (1 + Margin)
- Area is in square meters.
- UF approximates how well light reaches the target surfaces.
- LLF accounts for dirt, aging, and system losses.
- Margin adds headroom for aiming and plant growth.
How to use this calculator
- Measure the garden zone you want to accent.
- Pick a target lux based on the mood you want.
- Enter fixture lumens and approximate UF and LLF.
- Add a small margin if plants will grow or move.
- Review fixtures, spacing, and beam diameter together.
- Use the energy section to compare efficient options.
Recent calculations
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