Choosing a bathroom mirror size is a relatively easy task with the greatest considerations made for the style and size of your bathroom. While it is not necessary to use a measuring stick to determine the size of a mirror (Manufacturers make these calculations and clearly denote the dimensions on packaging materials.), it is still important to know the basic math used to measure a mirror so you can best determine its appropriateness for your vanity. For bathroom mirrors you purchase directly from a manufacturer, you have a range of options, styles, shapes and sizes from which to choose.

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Woman getting ready in bathroom
Close-up of bathroom sink
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Bathroom vanity

Step 1

Locate a mirror manufacturer and browse designers and collections. Common choices among several manufacturers include Meridian, Loft, Marina, Serenity and Studio. Online retailers like Target and Work2Beauty also offer a range of designers and collections.

Shower stall with glass door in domestic bathroom
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Interior of bathroom

Step 2

Decide which finish you want. Consider finishes such as brush chrome, brush nickel, brass and chrome polished. Match the finish to the general décor of your bathroom, including the lights and the color of walls or tiles. Make some consideration for hanging hooks and rings, shower curtains and floor mats as well as bathroom accessories such as toothbrush holders, soap dishes and glass holders if possible. For example, for an all-white bathroom, choose a chrome polished mirror to accentuate the white walls and tiles. When used in a small white bathroom, a chrome polished mirror tends to bounce the light from the white walls around the bathroom to create the effect of a larger space.

Bathtub
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Step 3

Evaluate the size of your bathroom to determine which size and shape mirror best complements the general size of your bathroom. Sizes vary from standard to custom and come with or without a frame. Common shapes include round, rectangular and oval as well as custom shapes.

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Woman looking in mirror

Step 4

Choose a mirror in relation to the vanity where it will be used. As a general rule, the mirror should measure several inches fewer than your vanity/sink area. For a medium-size vanity, choose a standard 24-inch mirror which can measure 24x20 inches, for example. Standard mirror sizes include 24 inches, 30 inches and 36 inches with a 30-inch mirror measuring 30 inches in height (width can vary depending on the shape of the mirror) and a 36-inch mirror measuring 36 inches in height. (Again, the width can vary depending on the shape of the mirror.)

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Man measuring wall

Step 5

Check the dimension by looking on the product description or measure the mirror from top to bottom (H or height) and left to right (W or width).