Foot-candles to phots
Type a value in foot-candles to see it in phots straight away, or type in the second box to convert back.
Loading the tool…
Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the foot-candles box.
- Read the result in phots as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
ph = fc × 0.001076391042
Multiply the value in foot-candles by 0.001076391042 to get phots.
Example
To convert 25 fc to phots: 25 × 0.001076391042 = 0.0269098 ph.
Conversion table
| Foot-candles (fc) | Phots (ph) |
|---|---|
| 1 | 0.00107639 |
| 2 | 0.00215278 |
| 3 | 0.00322917 |
| 5 | 0.00538196 |
| 10 | 0.0107639 |
| 20 | 0.0215278 |
| 25 | 0.0269098 |
| 50 | 0.0538196 |
| 100 | 0.107639 |
| 250 | 0.269098 |
| 500 | 0.538196 |
| 1,000 | 1.07639 |
About the units
- Foot-candle
- One lumen per square foot, exactly 10.763910416709722 lux, used in US lighting specifications.
- Phot
- The CGS unit of illuminance, one lumen per square centimeter, exactly 10000 lux.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many phots are in one foot-candle?
1 fc = 0.00107639 ph exactly.
How do I convert foot-candles to phots?
Use ph = fc × 0.001076391042. For example, 25 fc = 0.0269098 ph.
How many foot-candles are in one phot?
1 ph = 929.03 fc.
What is the difference between lux and lumens?
Lumens are the total light a lamp emits, while lux is how much of it lands on each square meter. A 1000 lumen lamp spread over 10 square meters gives 100 lux.
Why is a foot-candle about 10.764 lux?
A square foot is exactly 0.09290304 square meters, so one lumen per square foot equals 1 / 0.09290304 lumens per square meter.