High-Index Lenses: A Complete Guide
Choosing the right lens index makes a real difference in how your prescription glasses look, feel, and perform. High index lenses are designed to be thinner and lighter than standard lenses, offering improved comfort and a more refined appearance, especially for strong prescriptions.
All our high index lenses are crafted in our Canadian optical lab and reviewed by a certified in-house optician before every order ships.
Best for mild prescriptions.
Recommended for:
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Prescriptions with SPH up to: −2.50 / +2.50
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CYL up to 1.75
*This standard lens offers excellent optical clarity and durability for everyday wear. Ideal for lower prescriptions where lens thickness is minimal.
Best balance of thinness and value.
Recommended for:
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Prescriptions with SPH up to: −5.00 / +4.00
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CYL up to 3.00
*High-index 1.60 lenses are noticeably thinner and lighter than standard lenses, making them a popular choice for moderate prescriptions.
Designed for stronger prescriptions.
Recommended for:
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Prescriptions with SPH up to: −8.00 / +6.00
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CYL up to 4.00
*These very high-index lenses significantly reduce thickness and weight while maintaining sharp, high-definition vision.
Our thinnest lens option available.
Recommended for:
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Prescriptions with SPH beyond −8.00 / +6.00
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CYL up to 6.00
*Custom high-index lenses provide maximum thinness and comfort for strong prescriptions, with premium optics and advanced materials.
What Lens Index Should I Get?
As a general rule, the stronger your prescription, the higher the lens index you should choose. Higher index lenses bend light more efficiently, allowing the lens to be made thinner and lighter.
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Mild
prescriptions typically do well with 1.50 lenses
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Moderate
prescriptions benefit from 1.60 mid-index lenses
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Strong
prescriptions are best suited for 1.67 or 1.74 high-index lenses
*Choosing the right index helps improve comfort, reduce lens thickness at the edges, and enhance the overall look of your glasses.
Why Choose High-Index Lenses?
At Kraywoods, all our high index prescription lenses are crafted in our Canadian optical lab and reviewed by a certified in-house optician. Here's why they're worth it:
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Thinner
and lighter lenses
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Improved
comfort for all-day wear
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Reduced
edge thickness for stronger prescriptions
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Enhanced
aesthetics, especially in full-rim or oversized frames
*All of our high-index lenses are crafted with premium HD optics and can be customized with advanced treatments such as anti-reflective coatings, blue light filtering, photochromic lenses, sun tints, and therapeutic tints.
Frequently Asked Questions About High-Index Lenses
What are high index lenses?
High index lenses are prescription lenses made from a denser optical material that bends light more efficiently than standard lenses, allowing them to be made thinner and lighter for the same prescription power. The higher the index number, the thinner the lens. At Kraywoods, we offer four index options (1.50, 1.60, 1.67, and 1.74), all crafted in our Canadian optical lab and reviewed by a certified in-house optician before every order ships.
What is the difference between 1.50, 1.60, 1.67, and 1.74 lenses?
Each index represents a step up in how efficiently the lens bends light, which determines how thin it can be made. A 1.50 standard lens suits mild prescriptions up to ±2.50 SPH. A 1.60 high index works well up to -4.00 / +3.00 SPH. A 1.67 very high index covers up to -7.00 / +5.00 SPH, and our 1.74 ultra high index is best for prescriptions beyond that range. Our in-house optician reviews every order to confirm the right index for your prescription.
What lens index do I need for my prescription?
As a general guide: 1.50 suits prescriptions up to -2.50 / +2.50 SPH; 1.60 is ideal up to -4.00 / +3.00 SPH; 1.67 covers up to -7.00 / +5.00 SPH; and 1.74 is recommended for anything beyond that. Cylinder power from astigmatism also affects thickness, so your ideal index may vary. If you are unsure, contact us at customercare@kraywoods.com and our certified optician will guide you.
Are high index lenses worth it?
For anyone with a moderate or strong prescription, absolutely. Standard 1.50 lenses become noticeably thick and heavy at higher prescriptions, affecting both comfort and appearance. High index lenses reduce that thickness significantly — a 1.74 lens can be up to 50% thinner than a standard lens. At Kraywoods, all high index lenses include anti-scratch and anti-reflective coatings at no extra cost.
Do high index lenses affect vision quality or clarity?
No — when made with premium HD optics, high index lenses provide the same excellent clarity and sharpness as standard lenses. At Kraywoods, every lens is crafted in our Canadian optical lab and reviewed by our certified in-house optician to ensure your prescription is accurately reproduced without any compromise to optical quality.
Are high index lenses heavier than standard lenses?
High index lenses are actually lighter than standard lenses. Because the higher refractive index allows the lens to be made significantly thinner, the overall weight is reduced. This is one of the primary reasons high index lenses are recommended for stronger prescriptions — better vision correction in a lighter, more comfortable package.
What coatings are included with high index lenses?
All Kraywoods high index lenses come with two coatings included at no extra cost: anti-scratch to protect lens surfaces from everyday wear, and anti-reflective to reduce glare and improve visual comfort. These are applied to every lens regardless of index level, so your lenses are fully protected from the moment they arrive.
Can high index lenses be customized with tints or special coatings?
Yes. In addition to the standard coatings included with every order, Kraywoods high index lenses can be customized with photochromic lenses, blue light filtering, prescription sun tints, and therapeutic tints. All options are available across all four index levels, so you never have to compromise on lens technology to get the features you need.
Do high index lenses work for astigmatism?
Yes, high index lenses are fully compatible with astigmatism prescriptions. Cylinder power contributes to lens thickness in addition to sphere power, which is why a higher index is often recommended even for moderate prescriptions with significant astigmatism. Our certified optician reviews every order to ensure the right index and lens design is applied.
How do I submit my prescription when ordering high index lenses?
Select your preferred frame, click "Select Lenses," choose your lens type and preferred index, then upload your prescription as a PDF, JPG, or PNG, or enter your details manually. Make sure your prescription is valid and includes your pupillary distance (PD) for accurate lens positioning. Every order is reviewed by our certified in-house optician before production begins.
What is the warranty on high index lenses?
All Kraywoods high index lenses are backed by a 12-month warranty covering manufacturing defects. If you experience any issues within the warranty period, contact us at customercare@kraywoods.com and our team will make it right. Cleaning with a microfibre cloth and storing in a protective case will also help extend the life of your lenses.
Where can I learn more about high index lenses and high prescription glasses?
If you have a strong prescription and are ready to shop, visit our high prescription glasses collection where you can browse eco-friendly frames compatible with 1.67 and 1.74 high index lenses. Every pair ships free worldwide, is backed by a 14-day return policy and 12-month warranty, and is reviewed by a certified optician before it leaves our Canadian lab. For any questions, reach out at customercare@kraywoods.com.
