Part of planning for retirement is a math exercise -- figuring out how much money you have, how much you need and how to best save enough to build a big enough nest egg before you hang up your work boots.
It's not calculus, but figuring this out without help isn't easy either. Fortunately, there are dozens of free online calculators that will help you. Here are six of the best.Get on the Right Path
The first step is figuring out how much you have to save to pay the bills while you rock on the porch. If you want to take advantage of the wonders of compound interest, you need to start early.
Predicting accurately what life will be like in 40 years is practically impossible, but if you save without any kind of plan, you won't know whether you are even headed in the right direction. So even if you're just getting started on a career and retirement seems ludicrously far in the future, try out one of these calculators that helps you measure how much you need to save to avoid an all-kibble diet.
My favorite is the retirement income calculator from T. Rowe Price. It allows you to see the impact of changing various factors, including the amount being saved and the age you retire. It also makes it easy to factor in money from things other than savings, including Social Security, pensions and even inheritances (if you think Mom and Dad will come through in the end).
Measure How You Are Doing
Once you have a few bucks in your 401(k) and other savings accounts, then you should start worrying about how to invest them. Fidelity Investments offers an investment analysis tool that helps both customers and noncustomers decide whether they're putting their savings in the right places based on their investment goals, risk tolerance and how far from retirement they are. Plugging in all the information is a lot of work, but the results are enlightening.
Consider Social Security
Social Security is a big part of most people's retirement plan. Deciding when it makes the most sense to take your benefits and coordinating your strategy with that of your spouse can increase your lifetime net by thousands of dollars. SSCalc.net isn't the most sophisticated Social Security calculator out there, but it is the probably the best free one. If you're figuring both you and your spouse's draw, plug in the highest earners' numbers first and the lower earners' numbers as the "spouse."
Check Out Your 401(k)
BrightScope rates 401(k) plans and offers ideas for making your plan stronger. If you can't do that, you can at least use the tool to choose the best investments you're offered.
See the Damage Inflation Can Do
Inflation can wipe out your retirement plan. WalletPop offers a calculator that measures its effects so you can modify your savings strategy to fight it.
How Much Does an Immediate Annuity Pay?
Figuring out how to turn retirement savings into a monthly paycheck is tricky for many retirees. One way is to buy an annuity with part of your savings. ImmediateAnnuities.com calculates how much income you can get for your money. You don't have to register or part with much personal information, which makes this calculator a good deal.
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