See what it looks like by trying Asset Allocator yourself.

Improving the odds

There are some things you can do to improve your chances of meeting your goal.

Invest more now: If you can invest $30,000 now instead of just $20,000, your odds improve to 30%.

Up your monthly contributions: Maybe you can't come up with an extra $10,000 now. But if you invest an extra $200 each month, the likelihood of hitting the $1 million target rises to 42%.

Extend your number of years: Maybe you can't put in more money at all but can wait an additional five years before retiring. Your chances improve to 51%.

Become more aggressive: If you can't invest more money or time, try changing your portfolio mix.

So what is the best solution? Possibly it's a combination of all of the above. To see the effects of these adjustments, a tool like Morningstar.com's Asset Allocator can help. In Asset Allocator, click "aggressive" under Portfolio Asset Mix % and you'll get a portfolio that's even lighter in cash and bonds and heavier in stocks: 15% bonds, 55% large-cap stocks, 17% mid-/small-cap stocks and 13% foreign stocks. The odds of reaching your goal with that portfolio improve to 33% from 26%. The trade-off is an increase in short-term volatility: Your possible three-month loss steepens to an estimated 12.2%.

You can even adjust the portfolio mix yourself. Make it more or less aggressive by dragging the markers on the asset mix bar. As you make changes, the Asset Allocator numbers show you how reachable your goals are.

Limitations of asset-allocation tools

While online tools such as Morningstar.com's Asset Allocator certainly make asset-allocation decisions easier, they have limitations.

For example, if you use six different online asset-allocation tools, you're likely to get six different recommendations for what your asset mix ought to be. Why? Because every tool uses a different set of assumptions.

For example, Asset Allocator assumes a 2.5% inflation rate. Other tools use higher and lower inflation rates, and some will even allow you to choose your own rate. (For details on how Asset Allocator makes its calculations, check out the tool's Help section.) Different assumptions lead to different results.

Further, most online asset-allocation tools don't take taxes into account. That's because each investor's tax situation is different. But in the real world of investing, taxes are a huge issue. Realize that the final portfolio values you get from these various tools are generally pretax.

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Despite these limitations, online asset-allocation tools are a godsend to investors. They may not be 100% accurate to your specific situation, but they at least get you in the ballpark.