LIGHTING SCHOOL
Quick guides that make specs simple. Learn everything you need to get the right light for your home. Pick a topic to open the lessons.
Clear lighting guides that explain sockets/bases, bulb shapes, lumens, kelvin, dimming, and compatibility. Use Lighting School to understand the basics — then use the lamp finder to pick the right bulb with confidence.
Lumens
Brightness explained in plain language.
What is a lumen?
Lumens describe how much visible light a source produces.
More lumens = brighter light (independent of color temperature).
How many lumens do I need?
It depends on the room and purpose. Task lighting needs more than ambient lighting.
Use your old bulb as a reference and match lumens, not watts.
What’s the difference between lumens and lux?
Lumens are the total amount of light a bulb emits.
Lux is how much of that light actually lands on a surface (lumens per square meter).
Same bulb, different lux depending on distance, beam angle, and room layout.
Do more lumens always mean better lighting?
Not always. More lumens can help, but glare, beam angle, fixture design, and placement matter just as much.
A lower-lumen lamp placed correctly can feel brighter than a high-lumen lamp aimed in the wrong direction.
Why can a warm bulb feel dimmer than a cool bulb at the same lumens?
Our eyes often perceive cooler (higher Kelvin) light as more “crisp,” especially for reading and detail work.
Two bulbs can have the same lumens but feel different because color temperature affects perception and contrast.
How do I compare LED lumens to old incandescent bulbs?
Ignore watts and compare by lumens. As a rough guide:
- ~450 lm ≈ old 40W
- ~800 lm ≈ old 60W
- ~1100 lm ≈ old 75W
- ~1600 lm ≈ old 100W
Use it as a starting point—fixtures and shades can change how bright it feels.
What does “usable lumens” mean?
Sometimes brands list usable lumens (or delivered lumens) instead of raw output.
It reflects light that actually exits the bulb/fixture after losses (diffusers, optics, heat effects).
If two products list lumens differently, comparisons can get misleading—check if it’s “lumens” or “delivered lumens.”
Does beam angle affect how bright a bulb feels?
Yes—beam angle changes how concentrated the light is.
A narrow beam focuses light into a smaller area, often feeling brighter on that spot (higher lux), even if total lumens are the same.
Wide beams spread the light for softer, more even ambient lighting.
Why does a lamp look bright in the store but dim at home?
Store lighting, wall colors, ceiling height, and fixture/shade design can change perceived brightness.
Dark walls absorb more light; shades and diffusers can cut output; high ceilings spread light out and reduce lux on surfaces.
How many lumens should I aim for in common rooms?
It depends on the size of the room and the goal (ambient vs task). A simple starting point:
- Cozy ambient: lower lumens spread across multiple lamps
- Kitchen/task areas: higher lumens with good placement
- Reading/desk: focused light (good lux) matters more than huge total lumens
If you want, tell me the room type + size and I’ll suggest a lumen range.