What is the difference between R and PAR LED light bulbs?

LED reflector bulbs are available in two different types: R-type bulbs (these include R50, R63, R80, and R95) and PAR bulbs (this would include PAR20, PAR30, and PAR38).   Both of these bulb types are made to direct light forward rather than in all directions as standard light bulbs do.  But, they do have a few different characteristics as they are made to suit different applications.  We will go through these differences below.

Reflector bulbs are denoted with the “R” within their description and the number that follows refers to the diameter of the bulb in millimetres.  A R50 bulb for example would have a 50mm diameter.  These bulbs are often used for general all purpose lighting within a domestic environment.  You will find that they are used in ceiling fittings, wall lights and some recessed fixtures.  They have a reflective coating within the bulb that helps to produce a soft and diffused beam of light. 

PAR bulbs (Parabolic Aluminised Reflector) however are designed to produce a more focused beam of light.  PAR stands for Parabolic Aluminised Reflector and the number that follows refers to the diameter of the bulb but this is in eighths of an inch rather than millimetres.  They house a more advanced reflector design that produces a sharper and more controlled beam angle.  They are an ideal choice for spotlighting, accent lighting and other applications where you are looking to particularly highlight a specific location or object.

PAR bulbs are also made with stronger materials than standard reflector bulbs so that they can withstand a higher degree of weather conditions and outside bodies making them suitable for outdoor use and security lighting.  

Beam angles are another important difference between PAR and R reflector type bulbs.  R bulbs will usually have a wider beam angle making them a better choice for ambient lighting.  You will need PAR bulbs if you are looking for a narrow and focused beam of light.  

When comparing the bulbs to each other in terms of energy efficiency, both R and PAR LED bulbs will offer significant savings compared to incandescent and halogen bulbs.  LED bulbs can use as little as 10% wattage to produce the same amount of light as an incandescent or halogen bulb.  A 15W PAR38 for example has an equivalent wattage to an incandescent bulb of 100W. 

To summarise - the choice between R and PAR LED bulbs will depend on your specific lighting needs.  If you are looking for a bulb to use within the home that has a soft and wider spread R type reflectors bulbs will be best.  If you are looking for a bulb to use within a professional or outdoor environment with a focused beam of light, a PAR bulb will be the way to go.