Software for calculating an astigmatism treatment is operable upon execution by at least one processor to perform the following steps: receiving biometric information for a patient； determining based on the biometric information an astigmatic correction comprising at least one of (a) a position for one or more limbal relaxing incisions and (b) a power and an orientation for a toric intraocular lens (IOL)； generating an output comprising the astigmatic correction； receiving a selection of a different ratio of astigmatic correction attributable to the one or more limbal relaxing incisions and the toric IOL； determining an updated astigmatic correction including at least one of (a) an updated position for the one or more limbal relaxing incisions and (b) an updated power and/or orientation of the toric IOL.
