Illumination / ph → klx
Convert Phot to Kilolux
Convert illuminance on a surface between lux and foot-candles. Convert Phot (ph) to Kilolux (klx). Find the formula, worked examples, unit definitions, and practical guidance below.
How to convert phot to kilolux
Illuminance is luminous flux per area, not radiant watts per area. One lux is one lumen per square meter. Photometric weighting prevents a universal lux-to-watts conversion.
Use x for the value in ph, b for the intermediate value in lx, and y for the result in klx.
klx = ph × 10000 ÷ 1000
Worked examples
10 ph ≈ 100 klx
Step 1: (10 × 10000) ≈ 100000 lx.
Step 2: 100000 ÷ 1000 ≈ 100 klx.20 ph ≈ 200 klx
Step 1: (20 × 10000) ≈ 200000 lx.
Step 2: 200000 ÷ 1000 ≈ 200 klx.
Results are rounded to 12 significant digits. Converting units does not increase the precision of the original measurement. Very large or small values outside JavaScript’s finite numeric range are rejected.
About Phot
Phot (ph) measures illumination under the conventions above. The base value in lx is (x × 10000), where x is the numerical value in ph. Factors shown here are rounded for display; calculations use the stored factor.
About Kilolux
Kilolux (klx) measures illumination under the conventions above. The base value in lx is (x × 1000), where x is the numerical value in klx. Factors shown here are rounded for display; calculations use the stored factor.
Definitions and sources
Carry the same physical assumptions into subsequent physics calculations.
Phot to kilolux reference table
| Phot (ph) | Kilolux (klx) |
|---|---|
| 1 | 10 |
| 5 | 50 |
| 10 | 100 |
| 25 | 250 |
| 50 | 500 |
| 100 | 1000 |
| 1000 | 10000 |
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