What Lens Thickness Should I Choose?
The lens thickness of your glasses is an important consideration when ordering your next pair of prescription glasses online. Your lens thickness will differ depending on your prescription - the stronger/higher your prescription values, the thicker your lens.
You can mitigate thicker lenses caused by a strong prescription or PD by choosing a lens with a higher refractive index. This index is an indicator of how much light is bent as it travels through the lens. The more the light is bent, with a higher refractive index material, the thinner the lens can be.
Your lens options
There are four different refractive index options (thicknesses) to choose from when ordering your next pair of glasses:
Our standard lens, which you receive when ordering a Value, Bronze, or Silver Pack, has an index of 1.499.
Our thin lens, which you receive when ordering a Gold Pack, has an index of 1.60.
Our thinner lens, which you receive when ordering a Gold+ Pack, has an index of 1.67.
Our thinnest lens, which you receive when ordering a Platinum Pack, has an index of 1.74.
What lens thickness should I choose?
Short-Sighted
If you're short-sighted (negative SPH values), the edge thickness of your lenses will be much more visible and you'll see a clear benefit from selecting a higher refractive index lens.
For Sphere values between -2.50 and -4.00, we would recommend selecting at least a 1.6 index lens (Gold Pack). For values above this and between -4.00 and -6.00 we strongly recommend selecting a 1.67 index lens (Gold+ Pack), and for any prescription over -6.00, a lens of index 1.74 (Platinum Pack).
Outside of your lens selection, we also recommend choosing a full-rimmed plastic frame which will hide the edge thickness much better than a metal one. And try to choose a frame with a lens diameter below 50mm. The larger the diameter, the larger the edge thickness will be.
SPH Value |
Lens Pack |
Between -2.5 & -4.00 |
Gold |
Between -4.00 & -6.00 |
Gold + |
Over -6.00 |
Platinum |
Far-Sighted
If you're far-sighted (positive SPH values), the centre thickness of your lenses will be more prominent and you will also see benefits from selecting a higher refractive index lens.
For Sphere values between +2.50 and +4.00, we would recommend selecting at least a 1.6 index lens (Gold Pack). For values above this and between +4.00 and -6.00 we strongly recommend selecting a 1.67 index lens (Gold+ Pack), and for any prescription over -6.00, a lens of index 1.74 (Platinum Pack).
Outside of your lens selection, we also recommend choosing full-rimmed plastic frame which will hide the centre thickness much better than a metal one. And try to choose a frame with a lens diameter below 50mm. The larger the diameter, the larger the edge thickness will be.
SPH Value |
Lens Pack |
Between +2.5 & +4.00 |
Gold |
Between +4.00 & +6.00 |
Gold + |
Over +6.00 |
Platinum |
You can select any of these packages with any strength of prescription, and the choice is entirely yours. However, if you have a +/-6.00 and above values with a bronze pack, your lenses may be thicker than you would wish for.
To keep your lenses as thin as possible and for best results - if your prescription is high, then stay away from semi-rimless frames or large frames where the lens diameter is large such as the aviators. This will always cause the lens to be thicker.
Please email us at or call us on 01489 572340 for any advice on which lens might be best.