There is a software program offered through tax software like HR BLOCK TAX software that I use each year. It is called Deduction Pro. When you use their software, this piece is available free to calculate all of your yearly donations. I have used it for years. You choose What you are donating from a list of items, The condition they are in and how much of it and it caculates it for you. However you file your taxes, ask a person or check out the software on tax deductions under Charitable Donations section and you will get good credit for it.