Social Security Benefit Calculator

This spreadsheet allows you to calculate your future Social Security benefit at any retirement age for any set of earnings (real or assumed, past or future). 

Simple instructions: Enter your birth year and a set of past or future earnings in the peach boxes in the table on the left. You can get your entire list of past earnings from Social Security itself, which is a good idea to do every year anyway to verify your earnings were reported correctly. If desired (for advanced users), enter non-zero assumptions for inflation (CPI-W and Average Wage Growth in the upper right table). If you change these inflation measures, enter any possible future earnings as the actual earnings you expect to receive. Otherwise enter your salary in today's dollars. The outputs will always be in terms of "today's" dollars however. The main output is the table and graph at the bottom right, which will illustrate your actual annual benefit based on any future hypothetical retirement date. The x-axis represents the age at which future earnings are not taken into account (i.e. because you are retired and no longer working). Each colored line on the graph represents the age you wish to START collecting a benefit. Age 62 is at the bottom, age 70 at the top.

The maximum amount of taxed earnings for each year is represented by the Social Security Wage Base (SSWB; officially known as the benefit and contribution base). The "Indexed" column represents the adjustment for wage inflation on that year's earnings. Only the top 35 years of indexed earnings (including zeros, if any) are used to calculate the benefit. The top 35 years are shown in bold if there are more than 35 inputs.

You cannot save the spreadsheet, but you can cut/paste the earnings into and out of it from elsewhere. Thus you can save your own table of earnings data and then paste into this calculator when you come back.

Additional information is after the spreadsheet.

You can use this calculator to calculate your "Primary Insurance Amount" (PIA) for you and/or your spouse, which for most of you is the benefit you can receive at age 67. You can then use this PIA to determine an optimal Social Security claiming strategy for free at Open Social Security. We here at 'DM' are big big fans of "free". And I also highly recommend the free Social Security Tools, which gives a very nice educational walkthrough and visual representation of how your Social Security benefit is calculated using your own data (or demo data, if you prefer).

INPUTS:

Boxes shaded in Peach can be edited. 

Enter a birthdate and a set of actual past and estimated future earnings.

You have the option to change the default assumptions for future price inflation (CPI-W) and wage inflation  (National Average Wage Index; AWI). 

The default assumptions of "zero" for each of these economic values is what the Social Security Administration uses in estimates they provide (e.g. their online calculators, and the estimate they mail and/or provide in your online account). However, the values in green in the table ("SS-CPI" and "SS-AWI") are the predictions which Social Security believes represent the most likely future scenario. You can play with these values to see how your future benefit is affected.

OUTPUTS:

1) AIME (averaged indexed monthly earnings), PIA (primary insurance amount) and Monthly Benefit based on claiming age (e.g. the table).

Note that if there are no earnings after age 61, the AIME and PIA will be the same.

2) The graph displays your future benefit based on the age you start collecting benefits. The top line is age 70, the bottom line is age 62.

For any given set of earnings/estimates you provide the graph will illustrate what your benefit will be if you stop earning at any age (e.g. "retirement", the x-axis). At that retirement age, your benefit will depend on the age you start to receive benefits (what I'm calling the benefit age), as represented by the set of age 62 to age 70 lines on the graph.

All outputs are in Sept 2017 dollars.

NOTES

This spreadsheet uses the most recently released 2016 Average Wage Index values, and the Sept 2017 CPI. Several test cases agree with anypia 2018.1. Let me know if you find errors!

Keep in mind this spreadsheet is meant to provide ballpark estimates of social security benefits, as well as to allow you simulate the effects of future price and wage inflation in order to convert benefits more "accurately" into "today's dollars". The estimates provided to you by Social Security assume no wage inflation or price inflation (although technically, those estimates are thus still in "today's dollars" under those assumptions). For most reasonable economic assumptions, the SS estimates provided to you by SS will underestimate your actual benefit, in some cases dramatically, especially for younger workers. 

The graphical output illustrates, in one chart, certain features such as: Bendpoints; The change in benefit based on claiming age and retirement date; The effects of additional earnings after the benefit date.

Due to differences in PIA rounding with cost of living adjustments (COLAs), my outputs may be off by $1-$2 for those older than 61.

We believe the calculator is "exactly" accurate for those with a Jan 2nd birthday, and January claiming date (but I do not attest to this claim). In this case, all earnings from the year prior and any delayed retirement credits are credited to the benefit age/year, and credited to the current year (even if some increases due to recent earnings, for example, may be paid retroactively)

There may be various "edge" effects which are not taken into account, and might make the calculated benefit a little off. Jan 1 birthdays for example, perhaps other first of month birthdays, etc. 

[A special thanks to an anonymous internet poster who calls himself "sscritic" who spent many hours with us in back and forth conversations when we believed there was an error in the spreadsheet because we couldn't match AnyPia's outputs. AnyPia is a downloadable software package provided by the Social Security Administration which calculates benefits. It turned out that our spreadsheet was correct and the error was with AnyPia.]