Illumination Converter
Use this free Illumination Converter to quickly get accurate results in seconds, free and instantly offline with no signup required ever, trusted by professionals in Austin, Chicago, Miami, Denver, Seattle, and New York for reliable daily use without accounts, subscriptions, limits, or delays on any device for everyday personal and business workflows daily.
Convert light levels instantly with this illumination converter for lux, foot-candles, and phots in lighting design and photography.
Calculator Inputs
About Light Units
Use this free Illumination Converter to quickly get accurate results in seconds, free and instantly offline with no signup required ever, trusted by professionals in Austin, Chicago, Miami, Denver, Seattle, and New York for reliable daily use without accounts, subscriptions, limits, or delays on any device for everyday personal and business workflows daily.
Illuminance is light landing on a surface. Offices target 300–500 lux; a bright sunny day hits 100,000. Convert between metric lux, imperial foot-candles, cgs phots, and the tiny nox for night-vision contexts.
Do not confuse illuminance (lux, on surfaces) with luminance (nits, emitted by screens) — different quantities entirely. Everything runs in your browser.
Anchors: 1 ft-cd = 10.7639 lux exact, 1 phot = 10,000 lux exact, 1 nox = 0.001 lux.
Refs: Moonless night 0.002 lux, street 15 lux, office 500 lux = 46.45 ft-cd, sunlight 100,000 lux.
Privacy: Fully local. No values leave device.
Limits: Photopic illuminance only. For luminous flux, use lumens tools.
Office compliance: Austin offices auditing $300,000 leases verify 300 to 500 lux at desks for code and comfort. Seattle streets reviewing $500,000 safety plans confirm 10 to 20 lux coverage on 09/22/2026.
Warehouse specs: Chicago warehouses speccing $2M high-bay lighting convert foot-candle bids to lux baselines. Denver museums guarding $40M collections cap galleries at 50 lux for conservation.
Wedding exposure: Miami photographers lighting $8,000 receptions meter lux to lock exposure before moments pass. New York studios balancing $100,000 sets match practicals to key ratios.
Anchor math: Foot-candles times 10.7639 equal lux; phots scale ten-thousandfold; nox handles thousandths for night vision.
Quantity discipline: Lux measures landing light, nits emitted light — mixing them voids compliance reports entirely.
Where it is used
Office 300–500 lux compliance audits, warehouse specs quoted in foot-candles, photography exposure planning, museum 50 lux conservation limits, street 10–20 lux safety reviews, and night-vision nox calculations Austin offices audit $300,000 leases, Chicago warehouses spec $2M lighting, Miami photographers light $8,000 weddings, Denver museums guard $40M collections, Seattle streets review $500,000 safety plans, and New York studios balance $100,000 sets.
How to use the Light Units
- Value — enter the value (e.g. 500).
- From — enter the value.
- To — enter the value.
- Calculate — press the Calculate button to see the result instantly above.
Formula
Anchor to lux: result = value × luxPer[from] ÷ luxPer[to]; 1 ft-cd = 10.7639 lux, 1 phot = 10,000 lux, 1 nox = 0.001 lux.
Examples
Office to US
Warehouse 30 ft-cd
Museum 50 lux
Frequently Asked Questions
- How many lux for office work?
- 300–500 lux for general office tasks, 750+ for detailed drafting. Corridors manage with 100.
- Lux vs lumens?
- Lumens measure light emitted by a source; lux measures what lands on each square meter. One lux equals one lumen per square meter.
- What is a foot-candle?
- Illuminance from one candela one foot away — about 10.764 lux. Still standard in US lighting specs.
- Phot used where?
- CGS legacy in photography. 1 phot = 10,000 lux. Rare in modern specs.
- Nox?
- 0.001 lux for night-vision thresholds. Moonless overcast is ~2 nox.
- Private?
- Yes. All math runs locally.