How many lumens does a bedroom need?
Updated
Bedroom lighting has two opposite jobs: helping you get dressed and tidy up, and not getting in the way of sleep. That is why the general light can be lower than in the living room, with reading light close to the bed, placed where it does not glare at whoever is lying down.
For a bedroom of 10.5 m² (3.5 × 3 m, about 113 sq ft) with light walls, plan on about 3,850 lumens, roughly 41 W of LED. The recommended range is 100 to 150 lux for general light and 300–500 lux at the bedside and mirror.
Recommended lux for a bedroom
| Where | Illuminance | Color temperature |
|---|---|---|
| General room light | 100–150 lx | 2700K to 3000K |
| Reading in bed, mirror and wardrobe | 300–500 lx | 2700K to 3000K |
How many lumens by bedroom size
Total lumens to reach an average of 120 lux, adding up every bulb in the room. Watts are for regular LED bulbs (about 95 lm/W). 1 m² ≈ 10.8 sq ft.
| Area | Light walls | Mid-tone walls | Dark walls | LED (light walls) |
|---|---|---|---|---|
| 8 m² (86 sq ft) | 3,250 lm | 3,850 lm | 4,500 lm | ≈ 34 W |
| 10 m² (108 sq ft) | 3,750 lm | 4,400 lm | 5,150 lm | ≈ 39 W |
| 12 m² (129 sq ft) | 4,300 lm | 5,000 lm | 5,800 lm | ≈ 45 W |
| 15 m² (161 sq ft) | 5,050 lm | 5,850 lm | 6,700 lm | ≈ 53 W |
| 20 m² (215 sq ft) | 6,300 lm | 7,200 lm | 8,150 lm | ≈ 66 W |
Calculate for your room
Lighting tips
- Pick 2700K (warm white). Bright cool light at night works against feeling sleepy.
- Keep a switch or lamp within reach of the bed so you never get up in the dark.
- Avoid a fixture right above the pillow: lying down, you stare straight into it. Move it toward the foot of the bed or use indirect light.
- In front of the wardrobe or mirror, boost to 300 lux or more to see clothing colors properly.
How the math works
Average illuminance (lux) is the light that reaches the work plane (table height, 0.75 m / 30 in), per square meter. Not all the light a bulb emits gets there: walls and ceiling absorb part of it, and LEDs lose output over time. The math follows the lumen method, the standard lighting design calculation:
lumens = lux × area ÷ (CU × MF)
- Room index (K): describes the room's shape. K = L × W ÷ [h × (L + W)], where h = ceiling height − 0.75 m. Small rooms and tall ceilings have a low K: more light hits the walls before reaching the table.
- Coefficient of utilization (CU): how much of the light reaches the work plane. It comes from a table that crosses K with wall reflectance (light ≈ 50%, mid-tone ≈ 30%, dark ≈ 10%), for a diffuse ceiling fixture and a white ceiling.
- Maintenance factor (MF): 0.8, to account for LED depreciation and dust.
Example: in a 3.5 × 3 m room with a 2.7 m ceiling (h = 1.95 m), K ≈ 0.83 and, with light walls, CU ≈ 0.41. For 120 lux: 120 × 10.5 m² ÷ (0.41 × 0.8) ≈ 3,850 lumens. Divided by 95 lm/W, that is about 41 W of LED.
The 3D simulator uses the same math, with the size and wall color you pick.
Read this before you buy
These numbers are an estimate for planning and comparing, not a lighting design. The math accounts for wall color, light loss over time and an average LED efficacy (95 lm/W), but it does not know which fixture you will use, its beam angle or where the furniture is.
- In the store, compare lumens on the box, not watts. Efficacy ranges from 80 to over 110 lm/W.
- Closed fixtures, frosted diffusers and dark shades deliver less light than the bare bulb.
- When in doubt, aim for the middle of the range and add a dimmer: you can turn light down, not up.
- For construction, major renovations or commercial spaces, talk to a lighting designer, architect or electrician.
Where the values come from
The math follows the lumen method in the IES Lighting Handbook (Illuminating Engineering Society) and CIE 52 on utilization factors. The lux ranges are comfort references for homes, based on ANSI/IES RP-11 (residential lighting), ISO/CIE 8995-1 / EN 12464-1 and the residential values of the former Brazilian standard NBR 5413. Workplace lighting standards do not regulate homes; treat the values as a starting point.
- The Lighting Handbook, 10th ed. (2011)
Illuminating Engineering Society (IES) · Lumen (zonal cavity) method, room index and coefficient of utilization. - CIE 52:1982 — Calculations for interior lighting: applied method
Commission Internationale de l’Éclairage (CIE) · Utilization factor from the room index and surface reflectances. - ANSI/IES/ALA RP-11-26 — Lighting for Interior and Exterior Residential Environments
IES / American Lighting Association · Recommended practice for home lighting: lux levels per room and task. - ABNT NBR ISO/CIE 8995-1:2013 — Iluminação de ambientes de trabalho, Parte 1: Interior
ABNT (Brasil) · ISO/CIE 8995-1 · Current Brazilian/ISO standard for indoor illuminance; basis for home office and circulation areas. - EN 12464-1:2021 — Light and lighting: Lighting of work places, Part 1: Indoor
CEN (Europa) · European counterpart, same concept of maintained average illuminance. - ABNT NBR 5413:1992 — Iluminância de interiores (cancelada em 2013)
ABNT (Brasil) · Replaced by NBR ISO/CIE 8995-1; still the most quoted residential lux reference in Brazil.
Frequently asked questions
What is the best light color for a bedroom?
Warm white, between 2700K and 3000K, which is more comfortable at night. If the bedroom is also where you study, add a 4000K desk lamp just for the desk.
Can I use LED strips in the bedroom?
Yes, as decorative or indirect light (behind the headboard, under the bed). Strips usually have few lumens per meter, so they rarely replace the main light; only count them if the manufacturer lists their lumens.
How many LED watts for a bedroom of 10.5 m² (113 sq ft)?
About 41 W of LED across all bulbs, for 3,850 lumens (120 lux with light walls). Efficacy varies between brands, so check the lumens on the box: that is what tells you how much light the bulb gives.
What color temperature for a bedroom?
Warm white (2700K–3000K) is the most comfortable before sleep. To compare in practice, the 3D simulator lets you change each bulb’s color temperature and see the effect in the room.