Open Social Security is a free, open-source Social Security strategy calculator.
The calculator runs the math for each possible claiming age (or, if you're married, each possible combination of claiming ages) and reports back, telling you which strategy is expected to provide the most total spendable dollars over your lifetime.
Please note that this calculator should not be the only analysis you do, as there are various factors that it does not consider, such as:
If you're interested in learning more about Social Security, you may want to read my book: Social Security Made Simple.
Mike Piper is the primary author of the calculator. Mike is a CPA in St. Louis, Missouri. He is the author of nine financial books, as well as the popular blog "Oblivious Investor." He is an occasional public speaker (usually about Social Security or tax planning), and he has been quoted as a Social Security expert in numerous publications (e.g., Wall Street Journal, AARP, Kiplinger, and several others).
Brian Courts has also made major contributions to the project, especially the color-coded graph that displays the relative desirability of various filing dates. Brian has been employed as a high school teacher and civil engineer, and has volunteered with the Peace Corps and Habitat for Humanity. He is currently retired.
For people really interested in the details of how this calculator works, I'd encourage you to check out the source code, available at the following link. (The README file is a good place to start.)
For those just seeking a summary explanation, let's consider the simplest example scenario: an unmarried person, using the calculator prior to age 62. For such a person, the calculator:
If the person is older than 62 when using the calculator, claiming strategies that are no longer possible (i.e., filing in the past) are eliminated from the analysis.
For a married couple, it's the same sort of process, but with more going on. Specifically:
Everything is done in "real" (i.e., inflation-adjusted) dollars. So there is no need for you to make manual inflation adjustments.
By default, all of the math is done using the SSA's period life table to calculate a person's probability of being alive at a given age. This is roughly appropriate for a person with an average life expectancy. (For reference, for a male currently age 62, median age at death with this table is age 83. For a female, it would be just under age 86.)
You also have a few other options though, which come from the Society of Actuaries' Commissioner Standard Ordinary (CSO) "unloaded" Tables:
Other parties are encouraged to use the code from this calculator for their own purposes, per the license below. You can download the source code here:
Copyright 2018-2020 Michael Piper (obliviousinvestor.com)
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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