Stop guessing how many fixtures to order. Use our lumens calculator and lighting simulator to learn how to calculate lumens for any room size. Type in your dimensions, pick the space type, and get an instant fixture count. This lighting calculator for room planning also works as a warehouse LED lighting calculator. From the same team that manufactures 600+ LED models and ships to 100+ countries.
600+ LED models across 5 product lines. Shipped to 100+ countries for wholesale distributors, hospitality projects, and government infrastructure.
Pick a lighting calculator to plan lighting for any space , from a single room to a full commercial project. Use the illumination calculator and lumens simulator to calculate lumens, determine foot candles, and plan warehouse LED lighting layouts.
Start here. Pick your room type, type in the dimensions, and get a fixture count before you pick up the phone to a supplier. Covers 10+ space types with CRI, CCT, and maintenance factor built in.
Open Calculator →Warehouses, retail floors, parking lots , handles commercial spacing and IP ratings.
Open →See how long until your LED retrofit pays for itself.
Open →Off-grid solar sizing: panel wattage, battery capacity, LED load.
Open →2700K or 4000K? Pick a room, get a recommendation.
Open →Check dimmer compatibility before you buy, not after.
Open →How long before L70? Factor in hours/day and ambient temp.
Open →Fixture spacing, wall distance, and ceiling layout in one go.
Open →See the light pool before you install. Includes reverse calculator.
Open →Calculate square footage and target lumens for your room. Get fixture quantities, CRI, color temperature, and maintenance factor recommendations. Then explore our ceiling light catalog to find fixtures that match your results.
Reference: Living 20 · Office 40 · Retail 50 · Workshop 75 lm/sq.ft
A cozy 15 lm/sq.ft (161 lux) sets the mood for winding down after a long flight.
How to calculate square feet: Length × Width (in feet). If using inches, divide by 144. If using meters, area is in sq.m (㎡)
Lights dim over time and dust builds up. MF accounts for this so your room stays bright enough years later, not just on day one.
Room Area
0.00 sq.ft.
Target Lumens (15 lm/sq.ft)
0 lumens
Maintained: 0 lm (MF 0.80)
Suggested Fixtures
0 pieces
Based on 800 lm per fixture
Est. power: 0 W
Color Temp (CCT)
2700K – Warm White
CRI (Ra)
Ra ≥80 – Good
IP Rating
IP20 – Indoor Dry
Based on IES wall wash rule of thumb: Setback = Wall Height ÷ 4, Spacing = 2 × Setback. Target illuminance: 200 lux, uniformity ≥0.25.
Setback
2.25 ft
from wall
Spacing
4.50 ft
between fixtures
Fixtures
3
along wall
Target Lux
200
uniformity ≥.25
Reference: ARTELDS architectural lighting guide. Professional wall wash systems can achieve 214 lux with 6 fixtures vs 12 for standard systems. High-quality optics reduce fixture count by 50%.
$0.00
Calculate illumination requirements for commercial, office, and outdoor projects. Includes IP rating and beam angle recommendations.
Reference: Warehouse 20 · Factory 30 · Showroom 50 · Parking 5 lm/sq.ft
50 lm/sq.ft (538 lux) is where showrooms live , bright enough for finishes and displays to read true.
Commercial LED panels typically output 800–1200 lm per unit.
Total Area
0.00 sq.ft.
Total Lumens (50 lm/sq.ft)
0 lumens
Suggested Fixtures
0 units
Based on 1200 lm per unit
Est. power: 0 W
Recommended Spacing
-ft apart
Enter dimensions to calculate
CCT
5000K
CRI
Ra ≥90
IP Rating
IP20
Beam Angle
60° – Medium
For high ceilings, downlighting or architectural pendant systems are recommended.
$0.00
Calculate illuminance at any distance from a light source, or find the lumens needed for a target lux level. Includes beam angle reference.
Narrow Beam
< 20° · Spot / Accent
Medium Beam
20°–40° · Wall Wash / Display
Wide Beam
> 40° · Flood / General
Common Beam Angles by Fixture Type
| Fixture | Narrow | Medium | Wide | Very Wide |
|---|---|---|---|---|
| Track Light | 8° | 15°–24° | 38° | 60° |
| Pendant | 15° | 24°–38° | 60° | 120° |
| Downlight | 15° | 24° | 30°–38° | 60° |
| Spike / Outdoor | 10° | 25° | 40° | 60° |
Use narrow beam (8°–15°) for accenting art and architectural details. Medium (24°–38°) for wall washing and retail displays. Wide (60°+) for general ambient lighting.
Candela
-cd
Illuminance (Lux)
-lux
Illuminance (FC)
-fc
Formula: Candela = Lumens ÷ [2π × (1 −cos(beam angle ÷ 2))]. Illuminance = Candela ÷ Distance². 1 footcandle = 10.764 lux.
Convert between lumens, watts, lux, candela, and footcandles instantly.
Equivalent Power
8.0 watts
Formula: Watts = Lumens ÷ Efficacy (lm/W)
Compare LED, CFL, halogen, and incandescent bulbs by efficacy, lifespan, cost, and color temperature.
| Bulb Type | Efficacy | Lifespan | Cost | Color Temp | Rating |
|---|---|---|---|---|---|
LED | 80–130 lm/W | 15,000–20,000 h | Low | 2700K–3500K | ★★★ |
CFL | 50–80 lm/W | 8,000–15,000 h | Medium | 2700K–3000K | ★★ ★ |
Halogen | 15–20 lm/W | 2,000–4,000 h | Medium | 2700K–3200K | ★★○ |
Incandescent | 10–17 lm/W | 1,000–2,000 h | High | 2700K–3000K | ★ ○★ |
Power required for the same brightness – LED uses about 80-90% less energy than incandescent.
| Lumens | LED (W) | CFL (W) | Halogen (W) | Incandescent (W) |
|---|---|---|---|---|
| 450 | 4–6 | 9–13 | 29 | 40 |
| 800 | 7–9 | 13–15 | 43 | 60 |
| 1100 | 9–12 | 18–22 | 53 | 75 |
| 1600 | 12–15 | 23–30 | 72 | 100 |
| 2600 | 18–22 | 35–45 | 106 | 150 |
For 1000 lm
8–10W
Saves ~85% vs incandescent
For 1000 lm
15–20W
Saves ~70% vs incandescent
For 1000 lm
50–57W
Saves ~30% vs incandescent
For 1000 lm
60–100W
Baseline
Not sure how to determine lumens for your space? This guide walks through how to calculate lumens step by step, covering foot candles, lumen per square foot, and total lighting requirements. You can also use the lumens calculator or illumination calculator above for instant results. Understanding the amount of light needed helps you choose the right LED lights for any room.
Measure the width and length of your room in feet, then multiply the width by the length to get square footage. For a 12×14 dining room, that is 168 sq ft. Also note your ceiling height and mounting height, as taller ceilings require more lumens to maintain the same illuminance level. If you measure in meters, multiply by 10.764 to convert to square feet. In lighting design, illuminance is often expressed in foot candles (fc), where 1 foot candle equals 1 lumen per square foot. The lighting calculator above handles all of this automatically when you enter room dimensions, including mounting height for high bay LED lights.
Different rooms need different brightness levels based on IES standards. The foot candles required vary by space: bedrooms need 15 lumens per square foot (1.5 fc), living rooms 20 lm/sq.ft (2 fc), kitchens 40 lm/sq.ft (4 fc), offices 40 lm/sq.ft (4 fc), and retail spaces 50 lm/sq.ft (5 fc). These recommended lumens ensure adequate visibility for each task type. LED lights are particularly effective at delivering high lumen output per square foot efficiently. If you want to know how to determine lumens without memorizing these numbers, simply select your room type in the lighting calculator and it applies the correct foot candles and lumen per square foot values automatically. The calculator estimates also account for the amount of light needed based on room type.
Multiply room area by the lumen per square foot requirement to get total lumens. For example, a 168 sq ft dining room at 30 lumens per sq ft needs approximately 5,040 total lumens. This is the total lighting load for the space. For rooms with ceiling height above 10 feet, increase the total lumens by 10-20% to compensate for light loss at greater distances. The lighting calculator performs this calculation instantly and also factors in ceiling height and mounting height for more accurate lumen output recommendations. This is how to calculate lumens for any space.
LED output depreciates over time, and fixtures accumulate dust. Apply a maintenance factor of 0.8 for clean environments (offices, homes) or 0.7 for normal environments (restaurants, retail). Divide your total lumens by the maintenance factor to get the initial lumens needed. A 5,040 lumen target with MF 0.8 means you need 6,300 initial lumens. The lumens calculator includes this adjustment automatically.
Divide total lumens by the lumen output of your chosen fixture to determine how many light fixtures you need. For example, 6,300 lumens ÷ 800 lumens per LED downlight = 8 fixtures. LED lights typically produce 800-1,500 lumen output per bulb depending on wattage. Consider beam angle, CCT (2700K-5000K), and CRI (80+ for general use, 90+ for retail) when selecting fixtures for your lighting design. The lighting calculator above provides fixture count recommendations and calculator estimates based on your room specifications, ceiling height, mounting height, and total lighting requirements. For warehouse applications, use it as a warehouse LED lighting calculator to determine high bay LED lights placement.
Skip the manual math. Use our free lumens calculator to get instant results.
Open Lumens Calculator ↑Short answer: it depends on what you do in the room. A bedroom? 15 lumens per square foot is plenty. A kitchen where you're chopping vegetables? You want 40. Living rooms sit around 20, bathrooms around 25. Just pick your room type in the lighting calculator above and it does the math for you. This lumens calculator for room size gives instant recommended lumens based on IES standards.
Length times width, that's it. A 12 ft by 10 ft room = 120 sq ft. Measuring in inches? Multiply length by width, then divide by 144. Working in meters? Same idea , length times width gives you square meters. (㎡)
Here's the quick reference we use: bedrooms 15, living rooms 20, bathrooms 25, offices 40, retail 50, warehouses 20, pathways 10, parking lots 5 lumens per square foot. These recommended lumens come straight from IES recommended practice , not something we made up. The lumens calculator above applies these foot candles and lumen per square foot values automatically.
CRI tells you whether colors look right under the light. If you're selling clothes or food, you need Ra 90+ , anything less and the reds go muddy. Offices and homes? Ra 80 is fine. Warehouses? Nobody's checking color swatches, Ra 60 works. The calculator above picks a CRI for you based on room type.
Rule of thumb: warm light for relaxing, cool light for working. Bedrooms and living rooms: 2700-3000K. Offices: 4000K. Retail and showrooms: 5000K to make products pop. Warehouses: 5000-5700K. Don't mix CCTs in the same room , the contrast looks jarring.
First digit blocks dust, second blocks water. Indoor dry areas: IP20 is fine. Bathrooms and kitchens: IP44. Covered outdoor areas like porches: IP54. Full outdoor exposure: IP65 minimum. Coastal or marine? Go IP66. Pick your space type in the calculator and it suggests the right rating.
Lights get dimmer over time , dust settles on fixtures, LEDs degrade. The maintenance factor accounts for this so your room stays bright enough years later, not just on day one. Clean spaces like offices: 0.80. Normal: 0.70. Dirty warehouses: 0.60. Skip this and you'll be back adding fixtures in 18 months.
Divide lumens by the efficacy rating. A good LED runs about 100-130 lm/W, so 800 lumens needs roughly 6-8 watts. CFLs are around 50-70 lm/W, halogens 15-20. The converter tool up the page handles this automatically.
Illuminance decreases with the square of distance. Double the distance = 1/4 the illuminance. The distance calculator above factors beam angle into the illuminance result.
LED, by a wide margin. A decent LED hits 100-130 lumens per watt; CFL manages 50-70; halogen barely 15-20. LED also lasts 25,000-50,000 hours vs 1,000 for incandescent. The cost difference pays back in under two years for most commercial setups.
Total lumens divided by per-fixture lumens. But here's the catch , you need to account for maintenance factor. Say your room needs 2,400 lumens and each fixture puts out 800. On paper that's 3 fixtures. But with MF 0.8, you actually need 3,000 lumens, so 4 fixtures. The calculator above does this automatically.
R9 is the red rendering score, and it's the one most LED manufacturers don't want to talk about. Plenty of bulbs claim Ra 80+ but score R9 below 30 , meaning reds look flat and lifeless. If you're lighting retail, food, or cosmetics, insist on R9 above 50. Premium LEDs hit Ra 96 with R9 above 95.
IK tells you how much of a beating a fixture can take. Parking lot bollards and pathway lights need IK08 minimum , they get bumped by cars and mowers. Coastal areas? Go IK09 with 316L stainless hardware, or the salt air will eat through the housing in a year.
Narrow beams under 20 degrees for accenting art and architecture. Medium 20-40 degrees for retail shelves and display cases. Wide beams above 40 degrees for general room lighting. The beam angle calculator shows you the exact light pool size for any angle and ceiling height.
The lumens simulator is the room calculator at the top of this page. Enter your room dimensions, select the room type, and the lighting simulator calculates total lumens, fixture count, and recommended foot candles instantly. It works as a lighting calculator for room planning, warehouse LED lighting calculator, and illumination calculator all in one. The calculator estimates include maintenance factor and ceiling height adjustments.
Yes, this tool works as a warehouse LED lighting calculator. Select the warehouse room type, enter the facility dimensions and mounting height, and the calculator determines the amount of light needed in foot candles and total lumens. It also recommends high bay LED lights placement based on ceiling height. The IES standard for warehouse aisles is 20 foot candles (about 200 lux), and the warehouse lighting calculator applies this automatically.
An illumination calculator measures light falling on a surface (illuminance in lux or foot candles), while a lumens calculator measures total light output from a source (luminous flux). Our tool combines both functions: it calculates total lumens needed for a room and converts to illuminance in foot candles. The lighting calculator also factors in mounting height, ceiling height, and maintenance factor for accurate results. Use it to calculate lumens, determine foot candles, and plan LED lights placement.
Learn how to calculate lumens using our lighting calculator. Enter your room size, pick the room type, and get instant calculator estimates for total lumens and fixture count.
Length times width. A 12 by 10 foot room is 120 sq ft of square footage. Measured in inches? Multiply and divide by 144. Don't forget to account for ceiling height and mounting height , it affects fixture choice more than people think.
Take your square footage and multiply by the lumens per square foot for your room type. Living rooms: 20. Kitchens: 40. Bedrooms: 15. These recommended lumens come from IES , not a guess. This is the core of how to calculate lumens using a lighting calculator.
Divide total lumens by your fixture's output. But add 20-30% for maintenance factor . LED lights dim over time and dust builds up. Skip this and you'll be adding fixtures in a year. The calculator estimates above handle this automatically. For pendant lighting, check our Chandelier Size Guide and Beam Angle Calculator for placement.
This page functions as both a lumens simulator and a warehouse lighting calculator. Use the tools above to calculate lumens for any room size, or follow the guides below for warehouse LED lighting and high bay LED lights planning.
Need to calculate lumens for a warehouse? Select "Warehouse" as the room type in the calculator above. The warehouse lighting calculator applies IES-recommended foot candles of 20 fc (200 lux) for warehouse aisles and 30-50 fc for loading docks. Enter your facility dimensions and mounting height, and the tool calculates total lumens, fixture count, and recommended high bay LED lights spacing. For warehouses with ceiling height above 25 feet, high bay LED lights are the standard choice. The calculator estimates include maintenance factor to account for dust accumulation common in warehouse environments.
High bay LED lights are designed for mounting height above 20 feet. Use the lighting calculator to determine how many high bay fixtures your space needs. For a 40×60 foot warehouse with 25-foot ceiling height, you typically need 6-8 high bay LED lights at 150W each, spaced 15-20 feet apart. The calculator factors in ceiling height, mounting height, and the amount of light required (foot candles) to generate accurate fixture counts. High bay LED lights deliver 15,000-25,000 lumens per fixture, making them ideal for warehouse lighting calculator applications.
The lumens simulator converts between foot candles and lux automatically. Here are common illuminance levels used by the lighting calculator:
| Space Type | Foot Candles | Lux | Lumens/sq ft | Typical Fixture |
|---|---|---|---|---|
| Warehouse aisles | 20 fc | 200 lux | 20 | High bay LED 150W |
| Loading docks | 30-50 fc | 300-500 lux | 30-50 | High bay LED 200W |
| Retail sales floor | 30-50 fc | 300-500 lux | 30-50 | LED track 30W |
| Office workspace | 30-50 fc | 300-500 lux | 30-50 | LED panel 24W |
| Residential living | 10-15 fc | 100-150 lux | 10-15 | LED downlight 12W |
| Parking lots | 5 fc | 50 lux | 5 | LED shoebox 150W |
The illumination calculator above uses these IES standards to automatically assign foot candles and calculate lumens per square foot based on room type. For warehouse LED lighting calculator applications, the tool also factors in mounting height for high bay LED lights spacing.
I was specifying track lighting for a 12-store retail chain and needed lux numbers fast. Ran six rooms through this in under ten minutes. The recommendations matched what our consultant quoted $2,400 to calculate. Wish it exported to PDF directly , had to screenshot the results for the client report.
We kept under-ordering fixtures for warehouse aisles because the old spreadsheet used a flat lumen-per-square-foot number. This tool factors in ceiling height and maintenance factor, which closed the gap. Took me three projects to trust it, but the numbers hold up in the field.
Handy for ball-parking before I send clients to the manufacturer. The CRI and CCT suggestions per room type save me a follow-up email. Would be better if it remembered previous calculations . I sometimes need to re-run the same room with tweaked dimensions.
Send us your product list or project requirements. Our sales team responds within 2 hours during business hours with a detailed quotation. No MOQ pressure for first-time buyers.
