How to Measure a Lampshade

Have you ever wondered how to measure a lampshade? We're going to de-mistify it for you! Naturally, I love lampshades because they're an easy and inexpensive way to update your decor. But buying one can be a bit confusing if you're not familiar with the terminology. If you've ever wondered what size shade to buy, or what the heck all of those different kids of fittings are (spider, uno, harp...huh?) this is for you!

Today's post comes to us from the Lamps Plus sister site, 55 Downing Street - here's their quick guide to measuring and fitting lampshades:
How to Measure a Lampshade: You'll need 4 measurements from your current shade when shopping for a new shade: the top diameter, the bottom diameter, the vertical slant, and the vertical height (see illustration above). These measurements are especially helpful when shopping online!
How to Choose the Right Size Shade for Your Lamp: Here are a couple of tips to keep in mind - the height of the shade should be approximately 3/4 the height of your table lamp base, and the width of the shade should extend past the widest part of the lamp base. Following these guidelines will ensure the proper proportions of shade to base.
How to Know What Lampshade Fitter to Buy: There are 3 basic types of lampshade fitters: spider fittings, uno fittings, and clip-on fittings (see illustration above.)
1. Spider Fittings: are used with harps. The harp attaches to the lamp base, and the spider fitting sits on top of the harp and is often secured with a finial that screws onto the top of the harp. Table lamps often come with the correct harp included.
2. Uno Fittings: are used on smaller table lamps, bedside lamps, and swing-arm lamps. An uno fitter attaches directly to the lamp socket.
3. Clip-on Fittings: are a specialty fitting seen on small accent lamps and chandeliers. The wire fitting simply clips directly onto the light bulb. Clip-on fittings are generally recommended with low-wattage bulbs.
If you have a lampshade sizing question that wasn't answered here, please leave it in the comments and we'll do our best to have our experts give you an answer.