‌How to Choose High-Index Lenses for Your Glasses‌

Selecting the right lenses for your glasses is essential for comfort, aesthetics, and optimal vision. High-index lenses, known for their thinner and lighter design, are an excellent choice for individuals with stronger prescriptions or those seeking a sleek, modern look.

However, understanding when and why to choose high-index lenses requires careful consideration. Here’s a step-by-step guide to help you make an informed decision.

What Are High-Index Lenses?‌

High-index lenses are made from advanced materials that bend light more efficiently than standard lenses. Measured by their refractive index (e.g., 1.60, 1.67, 1.74), these lenses are thinner and lighter because they require less material to correct vision. For example, a lens with a refractive index of 1.74 is significantly slimmer than a standard plastic lens (index 1.50), even for the same prescription strength.

1.56 Standard Index

This is our most basic lens type. It’s ideal for low prescriptions in the range of +2.50/-5.00 or below. If you have an extremely mild prescription, the standard index option will deliver the thinnest frame.

Keep in mind that this lens index only features 85%-90% UV protection in a clear lens. For 100% UV protection, you’ll want to select a higher lens index or a more advanced lens (such as our blue light-blocking lenses or photochromic lenses).

1.61 or 1.67 Common Index

When you have a medium or strong prescription, you need a high-index lens to keep your lenses thin. High-index lenses have good optical clarity, 100% UV protection, and excellent durability. They currently come in indices of 1.61, 1.67, and 1.74. All three lenses are made with similar materials, so the choice of the index comes down to your prescription strength.

A 1.67 high-index lens is best for +7.00/-9.00 or above. It can even be a good choice for people with low prescriptions who want the additional lens benefits mentioned above.

If you have a prescription that is +4.25/-6.75 or below, you’ll benefit from the thinness of a 1.61 high-index lens.

1.74 Strong Index

Strong prescriptions that are +9.25/-9.25 or above will work best with a 1.74 index lens. When you have a really strong prescription, a 1.74 high-index lens will be the thinnest option.