Lens Index
1.74 Index Lenses
Our thinnest lens — designed for high prescriptions of ±6.00 and above. Anti-reflective (MAR) coating included as standard, with optional upgrades available at checkout.
MAR Coating Included
Single Vision & Varifocal
In-house Glazing
Why choose 1.74
Our thinnest lens for high prescriptions
Suited to high prescriptions
Specifically designed for prescriptions of ±6.00 and above where thinner lower index lenses are not practical.
MAR coating as standard
Anti-reflective coating is included as standard — reducing glare from screens and oncoming headlights.
The thinnest lens we offer
The highest index lens available at Glasses Store — the maximum reduction in thickness and weight for strong prescriptions.
Single vision and varifocal
Available in single vision and varifocal. Note: bifocal lenses are not available in 1.74 index.
Understanding 1.74
What you need to know
What is a 1.74 index lens?
The 1.74 is the highest index lens available and bends light more efficiently than any lower index. This means the same high prescription can be achieved in the thinnest, lightest lens material — making a substantial difference for strong prescriptions.
Who is it for?
1.74 is designed specifically for prescriptions of ±6.00 and above. If you have a high prescription and have previously struggled with thick, heavy lenses, 1.74 will make the most significant improvement to both the appearance and comfort of your glasses.
What prescription does it suit?
Best suited to SPH and CYL values of ±6.00 and above. For prescriptions below ±6.00, the 1.67 delivers a very similar result at a lower cost. Note: bifocal lenses are not available in 1.74 — single vision and varifocal only.
Thickness comparison
How does 1.74 compare?
At 1.74 you are getting the thinnest lens possible. For high prescriptions the difference compared to lower index lenses is significant.
1.50
Standard ←
Up to ±2.00
1.60
Thin
±2.00 – ±4.00
1.67
Thinner
±4.00 – ±6.00
1.74
Ultra-thin
±6.00 and above
Prescription guide
Which index suits your prescription?
Use your SPH and CYL values from your prescription to find the right index. The coatings column shows what is included as standard at each level.
Lens index
Prescription range
Best for
Included coating
1.50
Up to ±2.00
Low prescriptions
Anti-scratch
1.60
±2.00 – ±4.00
Mild to moderate
Anti-reflective (MAR)
1.67
±4.00 – ±6.00
Moderate to strong
Anti-reflective (MAR)
1.74 ←
±6.00 and above
High prescriptions
Anti-reflective (MAR)
How to order
How to get 1.74 index lenses
1
Choose a frame
Browse our full range of frames from £10 and pick a style that suits you.
2
Select your lens type
Choose single vision or varifocal at the lens selection step. Note: bifocal is not available at 1.74 index.
3
Select 1.74 index
Choose 1.74 at checkout. MAR coating is included — add blue light filter, transition or sunglass tint if needed.
Ready to order your prescription glasses?
All lenses are glazed in-house by our qualified technicians. Next-day delivery available on single vision orders placed before 3pm. Frames from £10.
Available with
1.74 index available lens types
Single vision
For reading, distance or everyday use. The most common lens type.
Varifocal
Seamless correction at near, intermediate and far distances in one lens.
Bifocal
Not available in 1.74 index. Available up to 1.67 index.
FAQ
Frequently asked questions
Is 1.74 index the right lens for me?
If your prescription is ±6.00 or above, 1.74 will give you the thinnest, lightest lens possible. For prescriptions below ±6.00, the 1.67 delivers a very similar result at a lower price and is likely the better choice.
What coatings come with the 1.74 index lenses?
Anti-reflective (MAR) coating is included as standard with all our 1.74 index lenses. You can add a blue light filter, a sunglass tint, or transition lenses as optional upgrades at checkout.
Can I get Varifocal lenses in 1.74 index?
Yes. 1.74 index is available in single vision and varifocal. Please note that bifocal lenses are not available at 1.74 index — bifocals are available up to 1.67.
What is the difference between 1.67 and 1.74 index?
1.74 is thinner and lighter than 1.67 and is most beneficial for prescriptions above ±6.00. For prescriptions between ±4.00 and ±6.00, the 1.67 gives an excellent result at a more accessible price. Both indexes include anti-reflective coating as standard.
