Investing in mutual funds for retirement is never too late. And the Zacks Mutual Fund Rank can be an excellent tool for investors looking to invest in the best funds.

The easiest way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. Using the Zacks Mutual Fund Rank of over 19,000 mutual funds, we've identified three outstanding mutual funds that are ideally suited to help long-term investors pursue and achieve their retirement investing goals.

Let's take a look at some of our top-ranked mutual funds with the lowest fees.

Alger Focus Equity Y (ALGYX Quick QuoteALGYX - Free Report) : 0.6% expense ratio and 0.52% management fee. ALGYX is a part of the Large Cap Growth mutual fund category, which invest in many large U.S. companies that are expected to grow much faster compared to other large-cap stocks. ALGYX has achieved five-year annual returns of an astounding 17.85%.

Vanguard Growth & Income Investor (VQNPX): 0.39% expense ratio and 0.37% management fee. VQNPX is part of the Large Cap Blend section, and these mutual funds most often invest in firms with a market capitalization of $10 billion or more. By investing in bigger companies, these funds offer more stability, and are often well-suited for investors with a "buy and hold" mindset. With yearly returns of 12.99% over the last five years, VQNPX is an effectively diversified fund with a long reputation of solidly positive performance.

Goldman Sachs Small Cap Equity Insights I (GCSIX). Expense ratio: 0.84%. Management fee: 0.8%. Five year annual return: 10.91%. GCSIX is a Small Cap Blend mutual fund, and usually targets stocks with market caps of less than $2 billion, letting investors diversify their funds among other kinds of small-cap equities.

There you have it. If your financial advisor had you put your money into any of our top-ranked funds, then they've got you covered. If not, you may need to talk.