How to Choose Your Reading Glasses Strength (Diopter Guide)

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Short answer: reading-glass strength is measured in diopters (+1.00 to +3.50). A rough starting point by age: early 40s ~+1.00 to +1.25, late 40s ~+1.50 to +1.75, 50s ~+2.00 to +2.25, 60s+ ~+2.50 and up. Test before committing — the right power lets you read comfortably at ~14–16 inches without squinting or strain.

The quick diopter chart (starting points)

  • 40–44: +1.00 to +1.25
  • 45–49: +1.50 to +1.75
  • 50–54: +2.00 to +2.25
  • 55–59: +2.25 to +2.50
  • 60+: +2.50 to +3.50

These are guidelines, not prescriptions — everyone's eyes differ.

How to test the strength

  1. Hold reading material at your normal distance (~14–16 in).
  2. Try a strength: text should be crisp and effortless.
  3. Too blurry = go up; headache/eye strain = go down.

Tips

  • Buy slightly weaker if between strengths — you can hold things a touch closer.
  • Need different distances? Consider progressive lenses.
  • Big difference between your two eyes, or persistent strain? See an optometrist — readers won't fix everything.

FAQ

What if I'm between two strengths?

Choose the lower one and hold reading material slightly closer; it's easier on the eyes.

Recommended product
Pick your power in the Reading Glasses (Spring Hinge) → (durable flex hinges). More on choosing: best reading glasses guide. Browse Accessories.

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