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Contact Lens Calculator

Soft & RGP fitting with keratometry-based recommendations

Clinical Disclaimer: This calculator provides preliminary estimates only. Final lens selection requires clinical evaluation, slit lamp assessment, and practitioner judgment.

Lens Mode:

OD (Right Eye)

Spectacle Rx

Keratometry

Avg K: 43.63D | Corneal astigmatism: 1.25D

OS (Left Eye)

Spectacle Rx

Keratometry

Avg K: 43.38D | Corneal astigmatism: 1.25D

Typical: 12mm. Vertex compensation applied when |Sph| ≥ 4.00D.

Soft Lens Fitting Recommendations

OD (Right Eye)
Toric Recommended
Contact Lens Power
-3.75 -1.25 × 90°
Toric
Base Curve
8.6mm
39.24D
Diameter
14.2mm
Avg K: 43.63D
Avg K: 43.63D → BC 8.6mm, Ø14.2mm. Cyl -1.12D ≥ 0.75D → toric indicated.
OS (Left Eye)
SE Acceptable (Borderline)
Contact Lens Power
-4.00 D (SE)
Spherical
Base Curve
8.6mm
39.24D
Diameter
14.2mm
Avg K: 43.38D
Avg K: 43.38D → BC 8.6mm, Ø14.2mm. Cyl -0.52D < 0.75D → spherical SE.

What to Verify Next

1
Trial lens fit — movement & centration
2
Over-refraction with trial lens
3
Toric axis alignment (if applicable)
4
Customer comfort & vision assessment

Clinical Disclaimer: This calculator provides preliminary estimates only. Toric thresholds follow industry standards (≥0.75D cyl → toric consideration). BC and diameter suggestions are starting points based on keratometry. Final lens selection requires over-refraction, slit lamp evaluation, and practitioner judgment.