Fluorescent Light Bulb Sizes Chart

Find the light bulb base type you re looking for with this visual chart detailed illustrations of general bases fluorescent bases and specialty halogen base types.

Fluorescent light bulb sizes chart. There are 4 different fluorescent light options. Sizes range from t2 to t17. Shapes sizes and bases. Lamps are typically identified by a code such as fxxty where f is for fluorescent the first number xx indicates either the power in watts or length in inches the t indicates that the shape of the bulb is tubular and the last number y is the diameter in eighths of an inch sometimes in millimeters rounded up to the nearest millimeter.

The diameter of the tube is described in eighths of an inch as it is for incandescent lamps so a fluorescent lamp 1 inch in diameter eight eighths is a t8. The most common form of fluorescent lamp is a straight tube. T4 t5 t8 and t12. All led can be screwed in like traditional bulbs.

If you are using a 60 watt incandescent or a 13 watt compact fluorescent cfl you can switch to a 10 watt led bulb. Most tube lighting will have its size mentioned on an end of the tube. Here you have a simple light bulb replacement guide showing you how easy transitioning from your incandescent bulbs to leds can be.