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Equivalent Wattages of Lumen Output

Replacing your average household light bulb has become more complicated over the years. Energy saving technology like compact fluorescent and LED mean you can get a light bulb as bright as your old 60W incandescent that uses, for example, just 8 Watts of electricity.

In old incandescent technology there was a clear link between the light output of a bulb and the amount of power it used. A 100W bulb was brighter than a 40W bulb but this isn’t always the case anymore. To make sure we get the correct replacement bulb in terms of the brightness we need to think in terms of light output.

Light output is measured in Lumens and can be found in the specification of all the product pages on our website.

What wattage light bulb do you need?

To make sure you get the same brightness from your energy efficient bulbs, use this chart to compare the wattages of different technologies.*


2W - 4W

5W - 7W

8W - 10W

9W - 13W

13W - 18W

Compact Fluorescent  


















Lumens (lm)
lumen brightness

230 - 375 lm

400 - 500 lm

700 - 900 lm

900 - 1125 lm

1300 - 1500 lm


Using the chart we can see that if you want to replace a 40W incandescent light bulb with a compact fluorescent (CFL), you will likely need a 7W CFL.

Similarly, if you want to replace your 53W halogen light bulb with a modern LED, the LED will probably use between 9 and 13 Watts of energy.

In each case, the important factor when choosing the replacement is to get a similar Lumens rating. To replace the 40W incandescent with a CFL you’d be looking for one with about a 400 Lumen output. And for our LED example, you would need one with at least a 900 Lumens output.

* LED technology is constantly evolving so the wattages we have shown may become outdated. Just remember to match the lumen output and you'll always get the brightness you want. 

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