Opticalc Toric Contact Lens Calculator will help you improve your fitting skills when prescribing soft contact lenses.

Given a patient's refraction and vertex distance, it will tell you their ocular refraction corrected for vertex distance.

It then provides a recommended spherical contact lens power based on the patient's spherocylindrical refraction.

If you have a mislocating toric contact lens, Opticalc can tell you by how much the lens is mislocating, and suggest a new lens to order.

Once you enter the power of the patient's contact lens and the spectacle over-refraction, Opticalc will tell you by how much the lens
is rotating, and recommend the correct lens power to order.

Opticalc allows you to work in varying precision in both power and axis, depending on the parameter availability of the lens you are working with.

Use Opticalc to minimise the number of reorders required for your toric patients, make your initial lens selection for your sperical
patients more accurate, or use it to confirm that the lenses provided from the lab are correct.

Features freeform script entry. For example, entering "50" will automatically convert to "+0.50", entering -650 will automatically convert to "-6.50". Cyl powers are assumed to be minus, for example, entering "75" into a cyl power will be converted to "-0.75".

Also includes an Apple Watch app as a free bonus. The Apple Watch app is a stand-alone mini-version of the toric calculator. Enter the scripts and perform the calculations all from your wrist!

Please note that some contact lens calculators give incorrect answers. Opticalc uses the same calculations as can be found on this web page:
http://www.vco.org.au/misc/ophthalmicalc/OphthalmiCalc.html --- Unfortunately, this page seems to have now disappeared.