Having searched around online I found this; http://www.fedcalc.com/servlet/com.quantos.fcgui.csrs This looks to be one of the best CSRS calculators online.
I recommend http://www.money-zine.com/Calculators/Retirement-Calculators/CSRS-Retirement-Calculator/ as a brilliant calculator for working out your retirement amount.
It is the older United States Government retirement system. The U.S. government maintains two retirement systems for their employees-the Federal Employees Retirement System (FERS) and the Civil Service Retirement System CSRS. CSRS is only available to federal workers who were in the plan before 1987.
Depending on whether you were employed under FERS or CSRS along with length of employment, unused sick time, taxability as well as other factors all play into how you calculate your federal retirement. The best tools are found at http://federalretirement.net/annuity.htm
You can go online to find a retirement planning calculator at moneycentral.msn.com/retire/planner.aspx. Another useful website is www.americanfunds.com/retirement/calculator/index.htm
You can find a free retirement planning calculator at either moneycentral.msn.com/retire/planner.aspx or www.americanfunds.com/retirement/calculator/index.htm. Fool.com and Vanguard offer retirement calculators online. These are free to use.
Retirement calculators are a great tool to plan for your retirement. If you go to the MSNBC website they have a free retirement calculator that has all of the necessary tools.
You can find a retirement saving calculator online, at the web page called Kiplinger. Their retirement saving calculator will help you estimate savings and determine how much more you need to save each month to reach your retirement goal.
You can go to moneycentral.msn.com. They offer a reliable and effective retirement planning calculator.
As a federal retiree with frozen CSRS, you need the military retirement document.
If you are interesting using a retirement calculator there are many websites that offer them. You can find them on websites such as TDbank and CIBC. Both which are reliable.
You can find an FERS retirement calculator at the following sites I found for you to look at. Here are the sites you can look at www.fedcalc.com/fers.jsp ,www.fedcalc.com/
Massmutual.com offers online retirement planning calculators.