How to Measure Frames for Glasses

Frames come in many sizes and shapes and it is important to make sure your frame fits you properly to ensure that you get the best vision possible with your lenses. In addition to frame size, you must take into consideration the strength of your prescription. Understanding frame measurements help you to select the best-size frame for your glasses.

Things You'll Need

• Ruler with scale in millimeters

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Instructions

• 1

  Decide if you want your frame to be smaller or bigger than your current frames, if you wear glasses, and hold your old frame up to potential new frames to compare.

• 2

  Select a variety of frames that you like, picking out at least five or six so that you have a better chance of finding one that fits you properly.

• 3

  Look for four numbers on the inside of the bridge of the frame, usually a set of two numbers separated by an x or a small square. Frames are measured in millimeters (mm). The first two numbers are the lens size (anywhere from 36 mm to 58 mm), and the second two are the bridge, measuring 14 to 24 mm.

• 4

  Keep your frame size smaller to mid-sized if you have a stronger prescription, usually anything higher than a sphere or cylinder power of 2.00 on your optical prescription. Small to mid-sized frames would be a lens measurement below 50 mm.

• 5

  Use a ruler with millimeters or an optical ruler to measure lens width if numbers are rubbed off the frame. Lens width is the widest point across the lens, usually from the inside edge of the rim measured from the ear side of the frame to the inside edge of the rim by the nose.

• 6

  Determine the proper temple length---the part of the frame that goes over your ears. Temples are also measured in millimeters and will range from 135 to 150 in 5 mm increments. The number is stamped on the temple or can be measured with your ruler.