Illuminance Converter
Convert illuminance between lux, foot-candle, phot and nox.
- Runs locally in your browser
- No upload required
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Supported formats
Privacy
Runs entirely in your browser. Your input is never uploaded, stored, or sent to a third party.
1 phot equals 10000 lux (lx).
How it works
- Expressed the source unit in lux using its exact factor.
- Divided by the target unit expressed in lux.
- Rounded the result to 12 significant digits.
1 phot = 10000 lx- Both units measure illuminance, so the conversion is a single exact multiplication.
Methodology
- Express every unit as an exact factor to the lux base.
- Multiply the input by the source factor and divide by the target factor.
- Round the result to 12 significant digits so a convert-then-convert-back operation stays within floating-point tolerance.
Usage
- Enter the value to convert.
- Choose the source and target units.
- Read the converted value and the conversion formula.
Examples
These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.
Phot to lux
{
"value": 1,
"from": "phot",
"to": "lx"
}Foot-candle to lux
{
"value": 1,
"from": "fc",
"to": "lx"
}Nox to lux
{
"value": 1000,
"from": "nox",
"to": "lx"
}Limitations
Exact illuminance factors
Every illuminance unit is defined as an exact multiple of the lux, so the conversion is a single multiplication with no approximation beyond floating-point representation.
Frequently asked questions
- Which illuminance units does this converter support?
- It supports every unit listed in the From and To menus, each expressed as an exact factor to the lux.
- Why does the result show a formula?
- The formula shows the exact multiplication so you can verify the illuminance conversion by hand.
Sources
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