LED Light Bulbs: How to Choose the Right Globe
Watts no longer tell you how bright a globe is. Here is how to choose an LED bulb by lumens, colour, base and shape, how E27 LED globes differ, and what dimmable really means.
LED globes use a fraction of the power of the old incandescent globes and last many times longer. But because they use so little power, the watts on the box no longer tell you how bright they are. Choosing the right LED comes down to five things: brightness, colour, colour quality, base and shape.
Brightness: lumens, not watts
| Old incandescent | LED, approximate | Brightness |
|---|---|---|
| 25 W | 3–4 W | about 250 lm |
| 40 W | 4–6 W | about 450 lm |
| 60 W | 7–9 W | about 800 lm |
| 75 W | 10–12 W | about 1,100 lm |
| 100 W | 13–16 W | about 1,600 lm |
LED wattage for the same output varies between brands, so compare lumens on the pack.
Colour temperature
| Name on the pack | Kelvin | Feels like | Good for |
|---|---|---|---|
| Warm white | 2700–3000 K | Cosy, like old globes | Living, dining, bedrooms |
| Cool / neutral white | about 4000 K | Crisp, clear | Kitchens, laundries, garages |
| Daylight | 5000–6500 K | Bluish, very bright | Workshops, task areas |
Use one colour throughout a room so it does not look patchy. Some globes switch colour with the wall switch or an app.
Colour quality: CRI
The colour rendering index (CRI) shows how naturally a light shows colours, on a scale up to 100. CRI 80 is standard; CRI 90 or more makes skin, food, timber and artwork look noticeably better.
Bases
| Base | Type | Common in |
|---|---|---|
| B22 | Bayonet, 22 mm | Many Australian ceiling fittings and lamps |
| E27 (ES) | Edison screw, 27 mm | Pendants, lamps, imported fittings |
| E14 (SES) | Small Edison screw | Chandeliers, small lamps |
| B15 (SBC) | Small bayonet | Small lamps, some fittings |
| GU10 | Twist-and-lock, mains | Spotlights and some downlights |
The full comparison is in E27 vs B22 light bulb bases.
E27 LED globes
E27 is the most common base worldwide, so E27 LED globes come in the widest range of shapes, from standard A60 globes to large decorative filament globes for pendants. If your fitting is E27, check the maximum wattage on the fitting (LEDs will be far below it), the globe size against the shade, and whether you need a dimmable version.
Shapes
- A60 (classic): general use.
- Candle: chandeliers and small fittings.
- Round (G95, G125): large globes for bare pendants.
- Filament: visible LED filaments that imitate vintage globes; best on a dimmer.
Dimmable LEDs
Only globes marked dimmable should be used on a dimmer, and the dimmer must be LED-compatible; otherwise globes can flicker or buzz. Many older dimmers need replacing with LED-rated ones, which is a job for a licensed electrician.
Questions
How many lumens do I need?
As a guide, about 800 lumens replaces a 60 W incandescent globe, enough for a typical lamp or small-room pendant.
Is warm white or cool white better?
Warm white (2700–3000 K) for living areas and bedrooms; cool or neutral white (about 4000 K) for kitchens, laundries and workspaces.
What does E27 mean on a light bulb?
An Edison screw base with a 27 mm diameter.
Can I use any LED globe with a dimmer?
No. Use globes marked dimmable, with an LED-compatible dimmer.
