Sphere, often written as SPH , is the part of an eye prescription that shows the lens power needed to correct nearsightedness or farsightedness. A minus (-) sphere means nearsightedness, a plus (+) sphere means farsightedness, and 0.00 / plano means no spherical correction is needed.

Quick Scoop

  • SPH = sphere power.
  • It is measured in diopters.
  • Negative number = helps you see far away better if you’re nearsighted.
  • Positive number = helps you see near objects better if you’re farsighted.
  • The larger the number , the stronger the correction.

Example

If your prescription says SPH -2.50 , that means you need lens power to correct nearsightedness. If it says SPH +1.25 , that means you need help for farsightedness.

Extra note

Sphere only covers the main focusing power of the lens. Other parts like cylinder (CYL) and axis are used if you also have astigmatism.

If you want, I can also help you read a full glasses prescription line by line.