Authoritative definitions of the International System of Units and SI prefixes.
Dedicated unit pair
Phot to Nox
Convert ph to nx instantly, then review the formula, assumptions, and rounding guidance.
Light & sound unitsInstant result
Decimals
Formula result = input × 10000 ÷ 0.001. 1 ph = 10,000,000 nx
Common examples
One value, several units
Lux10,000 lx
Foot-candles929.0304 fc
Nox10,000,000 nx
Conversion table
| ph | nx |
|---|---|
| 1 ph | 10,000,000 nx |
| 2 ph | 20,000,000 nx |
| 5 ph | 50,000,000 nx |
| 10 ph | 100,000,000 nx |
| 25 ph | 250,000,000 nx |
| 50 ph | 500,000,000 nx |
| 100 ph | 1,000,000,000 nx |
Conversion chart
1 ph10,000,000 nx
5 ph50,000,000 nx
10 ph100,000,000 nx
25 ph250,000,000 nx
50 ph500,000,000 nx
Worked example
1 foot-candle equals approximately 10.7639 lux.
Unit definition
Phot (ph) One phot equals 10,000 lux.
Unit history
Phot is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert ph to lux.
3. Convert the base value to nx and apply your display precision.
Understand the result before using it
Phot to Nox converts a value measured in Phot (ph) into the equivalent value in Nox (nx). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = input × 10000 ÷ 0.001
Assumptions
- Phot and Nox represent the same illuminance quantity.
- The input is expressed in ph; the output is expressed in nx.
- The unit definitions and conventional relationship shown on this page apply.
Worked example
1 ph = 10,000,000 nx. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a ph measurement in a document that expects nx.
- Compare a phot value with a value reported in nox.
- Check the ph-to-nx arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Decibel sound-pressure level is logarithmic and depends on the stated reference pressure.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Phot to Nox?
result = input × 10000 ÷ 0.001 Using the displayed relationship, 1 ph equals 10,000,000 nx.
How many Nox are in one Phot?
One Phot is 10,000,000 Nox. The displayed digits may be rounded.
Can I reverse the ph to nx conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts nx back to ph.
Is the Phot to Nox result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.