Convert Phots to Kilolux

Convert Phots (ph) to Kilolux (klx) instantly and accurately.

Phots (ph)
Kilolux (klx)

Conversion Formula

klx = ph × 10

About Phots

The phot (ph) equals 1 lm/cm² = 10 000 lx. The CGS-photometric unit of illuminance. Pre-SI optics texts express daylight in phots: full tropical sunshine is ~10 ph (100 klx); overcast sky ~0.1-0.2 ph. Wholly superseded by lux and kilolux in modern standards. 1 ph = 10⁴ lx.

About Kilolux

The kilolux (klx) equals 1 000 lx. Outdoor daytime scale: overcast sky ~10-20 klx; direct mid-latitude sunshine at noon ~80-100 klx. Required for fine inspection work, surgery, and color-critical print evaluation (ISO 3664: 2 klx). Also the range for plant-growth LED systems at canopy level. 1 klx = 10³ lx.

Quick Reference Table

Phots (ph)Kilolux (klx)
1 ph10 klx
2 ph20 klx
5 ph50 klx
10 ph100 klx
25 ph250 klx
50 ph500 klx
100 ph1000 klx

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