Do you have one shade but need two? Or have a shade which is cracked or broken? If you still have the parts of your broken shade, in order to measure for a replacement, you might carefully tape it together with scotch tape. Please be careful not to cut yourself.
Many people measure around the shade, although Light Shades are not measured by circumference around. We could measure ours to see if it matches yours, but there are easy methods to help you learn which size you need…. Below is detailed instructions and photos to help you understand the terms, with a few examples of HOW to measure.
Measuring the light fixture shade holder is also simple. You measure straight across the middle from one INSIDE edge of the holder to the opposite INSIDE edge of the holder. Your Shade Fitter must be just slightly smaller than the Shade Holder. The easiest way is a ruler unless the light socket is in the way. If so use a caliper (see bottom photo). Turn it upside down with the prongs setting against the inside edges. Hold it tight, then turn it upright to read the diameter of the shade holder. OR if you don’t have a caliper, you can also use a straight strip of light weight cardboard, bend it around the inside edge of the holder, scotch tape it, then gently remove it to measure the outside edges of the circle you just made. That will show you the size that will fit in the holder.
Shades are measured by diameter, which means straight across the middle from one side to the other. If you are measuring your shade, measure OUTSIDE edge to OUTSIDE edge. That is how lighting shades are measured, to determine if they will FIT into a light holder or fixture..
For Height, set the shade on the table and stick a ruler down the middle, then lay another across the top, to make it easy to read the exact spot on the horizontal ruler. That height includes the fitter neck (part that goes into your fixture). I also give the fitter neck height in some listings, because sometimes it is needed, but it is always part of the total height of the shade. If you can not put the ruler down the middle, set it against on side and extend another across the top so they meet. You should then be able to see the height on the standing ruler.
Top Rim Width or opening can be determined easily by laying a ruler across the middle of the top.
Neck Opening is a little harder. If you don’t have a caliper with arms long enough to extend into the neck, you can use another trick. Cut a piece of paper or cardboard long enough to reach down into the neck. Place it inside the neck, making a circle against the interior. Use scotch tape to secure it enough that you can pull it out, stand it on a table and measure across it, just as you did for the top rim. That will tell you the diameter of the inside of the neck which a chimney must fit through. The same method or a caliper can be used to determine the inside of a fitter, if you need to make sure a socket or candle will fit through.
To learn the Bulge (widest part) of your shade, find a piece of paper that is larger than the width of the shade. Lay it on a shelf or table that is against a wall, then push the paper against the wall. Now set your shade on it, also up against the wall. Stand a ruler upright against the opposite side, as shown in the photos. Make sure you are holding it reasonably straight up and down, then mark the paper on the shade side of the ruler. Remove the shade and measure your paper from the wall edge to the mark. You now have the diameter of the bulge of your shade.
For some shades, you may need to know the Fitter Height. It may be a type which must fit down into an opening where there may be lamp parts that might prevent it from seating correctly. Just use a ruler, against the side of the fitter, and measure from the fitter edge to the spot where the shade starts to bulge outward.
A Fitter diameter (part that fits into the shade holder) is usually easy to measure. Lay your ruler across the middle, or use a caliper to measure from OUTSIDE edge to the opposite OUTSIDE edge. You could also use a pencil to draw around the fitter. Then measure straight across the middle of your circle, which will give you the diameter of the fitter.
There are many other types of shades, but all are measured in a similar manner.
Remember…. The Fitter is always measured straight across the middle from outside edge to outside edge, and must be slightly smaller in order to fit into a holder which is measured from inside edge to inside edge.