Lux to Phot Converter
1 lux is exactly 0.0001 phots. Convert lux (lx) to phots (ph) below: type a value and the result updates as you type.
lx to ph calculator
Result
Lux to Phot conversion
1 lx = 0.0001 phone lux in phots
1 ph = 10000 lxone phot in lux
Lux (lx): SI unit of illuminance: one lumen per square meter. Office lighting is typically around 500 lx.
Phot (ph): CGS unit of illuminance: one lumen per square centimeter, exactly 10,000 lux.
Source:Lux: SI Brochure, 9th edition (BIPM, 2019); Phot: NIST Special Publication 811 (2008), Appendix B.8
How to convert lux to phots
To convert lux to phots, multiply the number of lux by 0.0001.
Formula
ph = lx × 0.0001
Examples
- 5 lx = 5 × 0.0001 = 0.0005 ph
- 25 lx = 25 × 0.0001 = 0.0025 ph
- 100 lx = 100 × 0.0001 = 0.01 ph
Lux to Phot conversion table
| Lux (lx) | Phot (ph) |
|---|---|
| 0.1 lx | 0.00001 ph |
| 0.5 lx | 0.00005 ph |
| 1 lx | 0.0001 ph |
| 2 lx | 0.0002 ph |
| 3 lx | 0.0003 ph |
| 5 lx | 0.0005 ph |
| 10 lx | 0.001 ph |
| 20 lx | 0.002 ph |
| 25 lx | 0.0025 ph |
| 50 lx | 0.005 ph |
| 100 lx | 0.01 ph |
| 250 lx | 0.025 ph |
| 500 lx | 0.05 ph |
| 1000 lx | 0.1 ph |
Values rounded to 10 significant digits where needed.
Frequently asked questions
- How many phots are in one lux?
- One lux is exactly 0.0001 phots.
- How do I convert phots to lux?
- To convert phots to lux, multiply the number of phots by 10000. The formula is lx = ph × 10000.
- Is this conversion exact?
- Yes. Both units have exact definitions and the factor 0.0001 is exact. Displayed results are only rounded when they have many decimal places.
- Which is larger, a lux or a phot?
- A phot is 10000 times larger than a lux. In other words, a lux is exactly 1/10000 of a phot.