How do you convert nox to foot-candles?

Use the formula: fc = nox ÷ 10763.91. This comes from chaining two conversions: 1 nox = 0.001 lux, and 1 foot-candle = 10.76391 lux. So 1 nox = 0.001 ÷ 10.76391 ≈ 0.00009290 fc.

The nox (nx) is a unit of illuminance equal to 0.001 lux (1 millilux). It was introduced to express very dim light levels — such as starlight at around 1 nox — without writing inconveniently small decimal fractions of lux. It is not an SI unit and is rarely used outside specialist photometry and older lighting literature.

What is a foot-candle?

A foot-candle (fc) is the imperial unit of illuminance: 1 lumen per square foot. It equals 10.76391 lux. Foot-candles are widely used in the US for lighting design, IESNA recommendations, and OSHA workplace requirements.

How many foot-candles is 1 nox?

1 nox equals approximately 0.00009290 foot-candles (or about 9.290 × 10⁻⁵ fc). To put that in context, a clear starry night produces roughly 1 nox, which is an extremely dim 0.0000929 fc — far below any occupied workspace minimum.

Is this the same as converting nox to lux and then to foot-candles?

Yes, exactly. The converter applies both steps in sequence: divide by 1000 to get lux, then divide by 10.76391 to get foot-candles. The single combined divisor is 10763.91, which keeps the calculation in one step with no intermediate rounding.

Nox to Foot-candles Converter

Enter a nox value and instantly get the equivalent in foot-candles, with the two-step formula and a dim-light reference table.

Nox to Foot-candles

Illuminance in nox (nx)

Enter a nox value above to see the result.

Formula: fc = nx ÷ 10763.91 | 1 nox = 0.001 lx = 0.0000929 fc

Dim-Light Reference Levels

Environment	Nox (nx)	Foot-candles (fc)

Click any row to load that nox value into the converter.

Summary

This converter transforms nox values into foot-candles in real time using the two-step chain: 1 nox = 0.001 lux, and 1 foot-candle = 10.76391 lux, so 1 nox = 0.001 / 10.76391 ≈ 0.0000929 fc. The nox is a non-SI unit for very dim illuminance — starlight territory — while foot-candles are the US-standard measure. All math runs in your browser; nothing is sent to a server. A reference table of dim-light environments is included so you can put your result in context.

How it works

Enter the illuminance value in nox in the input field.
The converter first converts nox to lux by dividing by 1000.
It then converts that lux value to foot-candles by dividing by 10.76391.
The combined formula is: fc = nox ÷ 10763.91.
The result updates instantly as you type.
Click any row in the reference table to load a sample value.

Use cases

Translate starlight or moonlight meter readings into foot-candles for US lighting reports.
Work with historical photometry data expressed in nox when targeting foot-candle specifications.
Design very low-light environments such as observatory surroundings or dark-sky preserves with US-standard measurements.
Evaluate night-sky quality survey data against foot-candle thresholds used in American standards.
Convert dim-light readings from environmental sensors into foot-candles for compliance documentation.
Compare illuminance values across unit systems in academic or cross-border lighting research.

Frequently Asked Questions

Last updated: 2026-07-14 · Reviewed by Nham Vu