The On-line Spectacle Buyers Guide. A complete guide to shopping for spectacles on-line. Part Two: How to choose a frame that fits You may already be a spectacle wearer. If so, try to select a new frame as close as possible to your existing frame size. A millimeter either way will not make a great deal of difference, especially on an adjustable pad bridge. Frame measurements will be indicated at various locations on your frame. The first place to look is on the sides. If you are lucky all three measurements will be together. Example: 48 x 18 x 135 or 48 ? 18 135 
The first number, 48, is the lens diameter (or eye size) in millimeters. The second number is 18; this refers to the bridge width. The final three figure number, 135, is the side length. The larger the numbers the bigger the frame. Side length is the overall length of the side measured from the centre of the dowel screw that secures the side to the front to the end tip, with the drop end or hockey end straightened out. When measuring a frame side it is not necessary to straighten the side to obtain the correct measurement. Simply place the ruler on top of the side and ‘walk' it around the outer radius of the bend to the tip. Side lengths as a rule tend to increase in 5mm increments. 
Other places to look are the inside of the bridge (especially on metal frames) or the inside of the right nose pad on plastics frames. The side length can sometimes be stamped on the inside of the plastic end tips. 
Other important measurements are the depth of the lens, from upper to lower rim and the overall width of the front of the frame. VERY IMPORTANT NOTE
Frame front width, known as FRONTAL WIDTH is the horizontal distance between the centres of the two dowel screws that secure the sides. This is the Overall Width measurement that we give for our frames. If you are unsure about sizing please feel free to contact us for advice, we can talk you through measuring your existing frame if the details have rubbed off! Bifocals & Lens Depth ~ If you are considering bifocals please be aware of lens depth. If the frame is very small and shallow, bifocals will not be very practical as neither the distance or reading portion of the lens will be large enough.
Compare your own frames measurements to those listed on our web site for a good fitting frame.
Other important notes regarding measurement
Side length is always measured as total length (as if the side were straightened) from the centre of the dowel screw that secures the side.
If you do not have a pair of glasses to go by, then you can easily take your own rough measurements. If you are unsure about sizing then a metal frame with adjustable nose pads is a good choice as it is easily adjusted.
Remember, you can always order frames on approval from Glasses4Less prior to purchase to save any disappointment.
If you're new to wearing spectacles you can always try on a few pairs in your local opticians to get some idea about size and style. to TOP | 
