How to Choose the Right Contact Lens Prescription?

Choosing the correct Prescription for colored contact lenses is essential for both vision clarity and comfort. Many buyers wonder: Can I use my eyeglasses prescription? What if I have astigmatism? What should I do if my eyes have different prescriptions? This guide will help you make an informed purchase decision, ensuring both safety and optimal vision correction.

1. Understanding Power (SPH) in Contact Lenses

The Power (SPH) of contact lenses is measured in diopters (D) and helps correct nearsightedness (-) or farsightedness (+):

• Negative (-): Example: -3.50D, corrects nearsightedness (myopia).
• Positive (+): Example: +2.00D, corrects farsightedness (hyperopia).
• 0.00 (Plano): No prescription, only for cosmetic enhancement.

💡 Key Buying Consideration: The prescription for colored contact lenses is often different from your eyeglasses prescription.

2. Do You Need Vision Correction?

• For cosmetic use only: Select 0.00 (Plano) lenses.
• For vision correction: Choose the appropriate Power (SPH) based on your latest contact lens prescription (not eyeglasses prescription).

3. Buying Lenses for Different Prescriptions in Each Eye

Most people have different prescriptions in each eye, so selecting the correct Power (SPH) for each lens is crucial.

• If both of your eyes have the same prescription, simply select the corresponding Power and purchase one pair of lenses.
• If your eyes have different prescriptions, HANIIX colored lenses allow you to choose different Power values for each eye.

To customize your prescription:

1. Go to the product page.
2. Look for the following image below.
   
3. Click on it to select and customize the Power for your left and right eye separately.

This feature ensures you get the perfect fit for both eyes without having to purchase two separate boxes.

4. Converting Your Eyeglasses Power to Contact Lens Power

Since eyeglasses sit about 12mm away from the eyes, while contact lenses rest directly on the cornea, adjustments are required for moderate to high prescriptions.

The "Glasses Power" column indicates the power of your current glasses prescription. If you do not have a contact lens prescription, the Vertex Conversion Chart provided below is a helpful tool that eye doctors, opticians, para-optometric technicians, etc., use as part of the process of determining what power to use for your contact lenses. It can quickly convert your glasses prescription to a contact lens prescription.

Vertex Conversion Chart
Glasses Power (SPH)	Contact Lens Power (SPH)
0.00 ~ ±4.00	No change
±4.25	±4.00
±4.50	±4.25
±4.75	±4.50
±5.00	±4.75
±5.25	±5.00
±5.50	±5.00
±5.75	±5.25
±6.00	±5.50
±6.25	±5.75
±6.50	±6.00
±6.75	±6.25
±7.00	±6.50
±7.25	±6.50
±7.50	±6.75
±7.75	±7.00
±8.00	±7.25
±8.25	±7.50
±8.50	±7.75
±8.75	±7.75
±9.00	±8.00
±9.25	±8.25
±9.50	±8.50
±9.75	±8.75
±10.00	±8.75
±10.50	±9.00
±11.00	±9.75

5. Choosing Lenses If You Have Astigmatism

If your prescription includes CYL (Cylinder - Astigmatism Power) and Axis, you'll need to choose the right type of contact lenses:

• You can still wear regular spherical lenses, but slight blurriness may occur.
• Many customers with mild astigmatism find regular lenses comfortable and visually acceptable.
• To enhance clarity, consider choosing an SPH 0.25D stronger than your contact lens prescription.
• Example:
  • Contact lens prescription: SPH -3.00D, CYL -0.50D,
  • Recommended choice: SPH -3.25D (regular spherical lenses, no CYL/Axis).
• 💡 Buying Tip: If you're unsure, consider trying a single pair first to test comfort and vision.

• You should use toric contact lenses for accurate vision correction.
• Ensure the lens matches your Power/SPH (Sphere), CYL (Cylinder), and Axis.
• Toric lenses are custom-made, slightly more expensive, and require precise fitting.