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As more and more LED lights come into the market, choosing the right LED is getting harder. So we have put together some tips for choosing the right LED light and the different aspects to consider when choosing an LED fitting or bulb.

Lumens not Watts

It used to be that wattage would tell you how bright a light would be. But with LEDs what you want to be looking at is the lumens. The higher the lumens the brighter the light will be. This is because watts is actually a measure of how much energy a light draws, so with LEDs which are more energy efficient, a 20W LED can actually be the same brightness/lumens as a 100W incandescent light

If a bulb has more lumens : watts (e.g. 2000 lumen : 20W vs 1000 lumen : 20W) a light bulb is more energy efficient.


Colour - Warm vs White vs Blue

Unlike standard light bulbs, LEDs come in a wide range of colours. You can choose a warm colour that is similar to traditional bulbs, or go for a cool toned LED closer to the colour of daylight. There are even some LED lights, for example like the Philips Hue light, that are customisable and can change colours.

There is ongoing research on the effects of different coloured LED lights on humans (see our 'Facts about LEDs' for some of these here). Some suggest white/blue toned lights for workspaces optimise productivity, and warmer tones in spaces like bedrooms help with sleeping.

Warmth of a light is measured in Kelvin; the higher the Kelvin the cooler the light.


The effects of different lighting on the colour of food - Left side = CRI 100, Right = CRI 80  |  Source:

Another way of assessing the colour of an LED is the Colour Rendering Index (CRI). CRI measures how accurately represented the colours are of what it's illuminating. For example an LED light with a CRI rating in the high 90s would show near normal colouring, while lights in the 80s or lower can cause things to appear slightly different colours e.g. colder and more blue/green.

Life expectancy

You're going to pay more for an LED light, but also you will pay more for a light of better quality and longer lifetime. Though the upfront cost is higher, investing in a better quality light with a longer lifetime will pay off in the long term.

Where is it going?


Not all LED lights are compatible with dimmer switches as they work by reducing energy sent to the light which may not affect brightness in the desired way. This is also the reason some LED lights may flicker, hum, or buzz when attached to a dimmer.
For this reason if you are putting an LED light where there is a dimmer you need to make sure it is a dimmable-LED compatible with the type of dimmer it is going with. Dimmable-LEDs do tend to cost more than the non-dimmable version. A LED specific dimmer may also need to be installed which could require an electrician to install.

IP rating

International Protection (IP) Ratings are defined in international standard IEC 60529 and classifies the degrees of protection provided against the intrusion of solid objects, dust, accidental contact, and water in electronic enclosures.  Depending on where the LED fitting is going a higher or lower IP rating may be required.

Some common IP ratings are:

Enclosed housing?

Though LEDs produce less heat than traditional bulbs, they do still produce heat. If this heat isn't dissipated it can damage the fitting and dramatically decrease the life expectancy. Usually the heat is pulled away into a heat sink and then keeps the bulb cool by dissipating into the air. However, if the fitting is placed in an enclosed space this mechanism may not work effectively. So it is important to make sure the fitting is approved for recessed or enclosed spaces if that is where it will be placed. Otherwise the promises of a long life will prove stunted.