Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Unit Converters
Lumens to Lux Converter (Light Intensity)
lux = lumens ÷ area (m²).
Lux = lumens ÷ square meters, if every lumen landed evenly on that patch. An 800 lm bulb over 10 m² is 80 lx on paper. Walls, shades, and inverse-square eating the corners are not in the slider.
Luminous flux
lm → lx
80 lx
A 800 lm bulb over 10 m² is 80 lx if none of it hits the walls. Rooms waste a lot.
- Lumens
- 800
- Area
- 10 m²
Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
Luminous flux
The “Luminous flux” value used in this tool’s formula. Adjust it to see results update live.
Area (m²)
The “Area (m²)” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
Lux = lumens ÷ square meters, if every lumen landed evenly on that patch. An 800 lm bulb over 10 m² is 80 lx on paper. Walls, shades, and inverse-square eating the corners are not in the slider. lux = lumens ÷ area (m²). Example: 800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
lux = lumens ÷ area (m²).
Example: 800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
When to use this Lumens to Lux
Common use cases
- Lux = lumens ÷ square meters, if every lumen landed evenly on that patch. An 800 lm bulb over 10 m² is 80 lx on paper. Walls, shades, and inverse-square eating the corners are not in the slider.
- Sanity-check with this case: 800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
- The relationship is: lux = lumens ÷ area (m²).
Localized examples
- Unit Converters: the example on this page uses the same formula as the widget.
What you get
- Fields: Luminous flux, Area (m²)
- lux = lumens ÷ area (m²).
- Example on the page: 800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
How to Convert Lumens to Lux Step-by-Step
- 1Enter Luminous flux, Area (m²). Use the values you have, not a catalog average, unless that is all you know.
- 2lux = lumens ÷ area (m²).
- 3Worked case: 800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
- 4Check which dictionary the other person is using — US or UK, decimal or 1,024 — then trust the number.
Governing formula
lux = lumens ÷ area (m²).
800 lm on 10 m² → 80 lx. 1600 lm on 4 m² → 400 lx.
Example: set Luminous flux = 800, Area (m²) = 10, then read the result.
Variable definitions
- value
Luminous flux
The “Luminous flux” field. Default 800; typical range 0–100000.
- areaM2
Area (m²)
The “Area (m²)” field. Default 10; typical range 0.01–1000.
- The conversion (lux = lumens ÷ area (m²).) does not pick US vs UK gallons, SI vs binary megabytes, or Mach at altitude for you. Read the footnote on the page.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
300–500 lx is a common office target. Measure at the desk, not at the lamp.
Related calculators
Unit Converters
- Foot-candles to LuxOne foot-candle is one lumen per square foot, 10.764 lux. US building specs still print fc; EU prints lux. A 50 fc classroom is about 538 lx.
- SI Weber Prefix ConverterMagnetic flux in webers. Transformers and search-coil experiments still write milliwebers. Maxwells are a cgs cousin on a different page. Prefixes here stay SI.
- Webers to Maxwells1 weber = 10⁸ maxwell. Tesla is flux density (Wb/m²); maxwell is the CGS flux. Old magnet catalogs still print Mx. New papers should not.
- Acres to HectaresUS farm ads in acres, EU paperwork in hectares. Divide acres by 2.471. Ten acres is 4.05 ha. A 160-acre quarter-section is 64.7 ha.
- Acres to Square FeetUS land: one acre is 43,560 ft², a chain-and-furlong leftover that refused to die. A quarter-acre lot is 10,890 ft². Multiply acres by 43,560. Soccer-field metaphors are not a survey.
- Appliance Running CostCost = watts × hours / 1000 × $/kWh. A 1,500 W space heater for 4 hours at $0.16/kWh is $0.96. The supply rate on the bill is the one that matters, not a national average.
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Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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