Lux (lx)
The lux (lx) is the SI unit of illuminance — one lumen of luminous flux per square meter on a surface.
Lux measures workplace lighting levels, photography exposure planning, and building-code minimum illuminance requirements.
Lux to Phot
Convert lux to phot instantly. Type in either field — results update live.
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illumination Lux Phot
1 lux = 0.0001 phots
Unit
Unit
Conversion table
Selected lx values converted to ph using the exact factor from this tool.
| lx | ph |
|---|---|
| 0.01 | 0.000001 |
| 0.1 | 0.00001 |
| 1 | 0.0001 |
| 2 | 0.0002 |
| 3 | 0.0003 |
| 5 | 0.0005 |
| 10 | 0.001 |
| 20 | 0.002 |
| 50 | 0.005 |
| 100 | 0.01 |
| 1,000 | 0.1 |
How to convert
Exact conversion factors in both directions, plus a worked example.
1 lx = 0.0001 ph
1 ph = 10000 lx
To convert lux to phot, multiply by 0.0001.
To convert phot to lux, multiply by 10000.
Example: convert 10 lx to ph
10 × 0.0001 = 0.001 ph
About these units
Short background on the units used in this conversion.
Phot (ph)
The phot (ph) equals 10,000 lux — a CGS unit of illuminance (one lumen per square centimeter).
Phots appear in older photometry and optical engineering references alongside lux and foot-candle.
Frequently asked questions
How many phots are in one lux?
One lux equals 0.0001 phots. Multiply your luxs value by 0.0001 to convert to phots.
What is the conversion formula?
ph = lx × 0.0001The reverse is
lx = ph × 10,000, using the same exact factors as this converter.Is this Lux to Phot converter private?
Yes. All calculations run locally in your browser. Nothing you type is sent to a server.