Philips PAR20 LED Bulb 5.5W=50W E27

Every light source from an LED to a simple wax candle has a beam angle. A beam angle is a measurement of how the light is distributed. GU10 LEDs and recessed downlights have a fairly narrow beam of around 40 degrees, anything within 5 degrees is classed as a medium beam.

A wax candle or traditional light bulb would have a beam angle of 360 degrees as the light shines all the way around but is less intense.

Combing brighter downlights with wider 60 degree beams allows you to space them out further, reducing the total amount of lights needed.

More information about beam angles.

CRI stands for Colour Rendering Index. It is a measurement of how well a light source can render the true colour of an object compared to natural light.

Rated out of 100, with an open flame or sunlight being a perfect 100. A light with 90 CRI and above would be classed as having high CRI, while 80 CRI is the standard for LEDs.

Read more about high CRI.

Colour temperature is a measurement of appearance. Measured in Kelvins, the lower the rating, the warmer the light appears. Choosing the right temperature can have a dramatic effect on a room.

2700K - Extra Warm White

Similar to a traditional incandescent light bulb or halogen. It has a more orange and warmer tone, with a ‘soft white’ appearance. Ideal for living rooms.

3000K - Warm White

Clearer, but still quite warm. This is the ‘new norm’ for general lighting and is the most popular option. If you’re unsure I’d recommend trying this one.

4000K - Cool White

Clearer, whiter and crisp; used in commercial locations including supermarkets. Cool white appears brighter than warm white as the LED is covered in less phosphor. It can make a room appear cold and clinical but used correctly (white walls etc) it can make a room appear cleaner and modern.

More information about colour temperatures.