The strength of reading glasses is measured in diopters, which is the unit of measurement that determines the strength of the lenses. Most over-the-counter reading glasses start at +1.00 as the lowest reading strength and increase in +0.25 increments. The power of reading glasses that you need depends on your specific needs, and it is important to choose the right strength to avoid unwanted side effects. Here are some methods to determine the strength of reading glasses you need:
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Diopter Reading Test Method: This is one of the easiest and most common methods for figuring out what strength reading glasses you need. Diopter test charts have rows of words ranging in text size that correspond to reading glasses strengths. When you reach a line that you can read clearly without any help from glasses, look at the strength next to it: This is the reading glasses strength you need.
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Eye Chart Method: Download the Reading Glasses Strength Chart PDF and print it out. Be sure to remove any corrective lenses or glasses. Hold the paper approximately 14 inches away from your face. Read the lines from top to bottom. The first line you have difficulty reading is an indicator of the strength that will probably serve you best.
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Power Straddle Assortment Method: Order three pairs of reading glasses with different strengths, including the strength you think you need and two additional reading powers in the identical frames. Experiment with the three powers you selected and see which works best for you under normal reading conditions. It often comes down to two powers that are hard to distinguish between. We find most people will select the weakest power.
There are also available reading glasses power charts that recommend the strength of reading glasses youll need depending on your age. However, it is important to note that the strength of reading glasses you need may vary depending on your specific needs, and it is always best to consult an eye doctor if you have any concerns.
