Lens thinning

What does 1.67 lens thinning mean?

1.67 is a high-index lens option used to make some prescription lenses thinner than standard plastic lenses.

Checked on 26 April 2026Reviewed by UK Glasses Guide editorial teamInformation only
Decision first

Should you choose this?

Buy the lens upgrade only when it solves a real comfort, appearance, glare or prescription problem. Skip it when the standard lens already does the job.

OptionTypical costChoose it forRisk level
Standard lensLowestMild prescriptions and spare pairsLow
1.6 / modest upgradeMediumModerate prescriptions or nicer finishLow to medium
1.67 / 1.74 or specialist coatingHigherStrong prescriptions, glare, driving or appearance needsMedium
Worth itstrong prescription, glare, driving or comfort need
Skip itmild prescription in a small frame
Safer alternativeoptician advice for complex lenses
Editorial reviewReviewed and updated by the UK Glasses Guide editorial team.
Source dateChecked on 26 April 2026.
CorrectionsSend a correction if retailer terms, pricing or delivery details have changed.
ImportantInformation only; use an optician for medical or fitting advice.

1.67 lens thinning verdict

Lens thinning is about lens index. A higher-index lens bends light more efficiently, so the lens can often be made thinner for the same prescription. 1.67 lenses are commonly offered for stronger prescriptions where standard lenses may look thick or feel heavy.

That does not mean every buyer needs 1.67. The right choice depends on prescription strength, frame size, frame shape, lens type, budget and whether the retailer explains the trade-off clearly.

May help

Moderate to strong prescriptions, larger lenses, rimless or semi-rimless frames, and buyers sensitive to lens thickness.

May be overkill

Low prescriptions, small round frames or spare pairs where standard lenses are already acceptable.

Best check

Ask whether frame size and prescription justify the upgrade, not just whether it is available.

Why frame size matters

Large frames can make lenses thicker at the edge for minus prescriptions. Choosing a smaller, rounder frame can sometimes reduce thickness more cost-effectively than paying for the highest lens index.

What to compare online

  • Whether the retailer recommends lens index by prescription strength.
  • How much the upgrade adds to the basket.
  • Whether coatings are included or separate.
  • Whether the frame is suitable for thinner lenses.
Standard lensOften fine for low prescriptions and backup pairs.
1.60 indexA common first thinning step for moderate prescriptions.
1.67 indexOften considered for stronger prescriptions or cosmetic thickness concerns.
1.74 indexUsually a more premium option for higher prescriptions, if available and suitable.

When to get advice

If your prescription is strong, you are buying varifocals, or you are choosing a very large frame, it is worth asking the retailer or an optician before paying. Lens thinning is useful when matched to the right frame, but it is not a universal upgrade.

Compare frame size and index before ordering

Use this guide with the retailer comparison and checkout checklist so the final basket, support route and return terms are clear.

Checked on 26 April 2026. Retailer information, comparison notes and source links are reviewed for buyer relevance, but prices, codes, delivery times and policies can change without notice.

Sources checked

This page is written as buyer information, not optical advice. Check current retailer terms and speak to a qualified optician if your prescription, eye health or fitting needs are complex.