Free Florida alimony calculator to estimate annual alimony payments and monthly alimony payments. This Illinois alimony calculator makes Illinois maintenance calculations using the Illinois alimony formula.Calculate alimony quickly and accurately with our state-specific alimony calculators. Get an estimate based on your state's guidelines for free. Learn about the types of alimony available in Florida and how judges decide which type to award, how much the payments should be, and how long they'll last. To calculate Illinois guideline maintenance, you must enter gross income, child dependent, and marriage length information into the calculator. Alimony Reform Enacted in Florida. Florida has just joined the cadre of states that provide a mathematical calculation for alimony. Get an estimate for alimony payments and duration. Get an idea on how much money a month you can expect to pay, and for how you can expect to pay it.