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, most reliable way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. The Zacks Mutual Fund Rank, which covers over 19,000 mutual funds, has helped us identify three outstanding options that are perfect for any long-term investors' portfolios that is retirement-focused.

Let's break down some of the mutual funds with the top Zacks Mutual Fund Rank and the lowest fees.

DWS CROCI US Institutional (DCUIX Quick QuoteDCUIX - Free Report) : 0.67% expense ratio and 0.43% management fee. DCUIX is a Large Cap Value fund. These funds invest in stocks with a market cap of $10 billion of more, but whose share prices do not reflect their intrinsic value. DCUIX has achieved five-year annual returns of an astounding 12.69%.

Fidelity Advisor Stock Select Allocation Cap M (FSJHX) is a stand out amongst its peers. FSJHX is a Large Cap Growth option; these mutual funds purchase stakes in numerous large U.S. companies that are expected to develop and grow at a faster rate than other large-cap stocks. With five-year annualized performance of 11.68%, expense ratio of 1.04% and management fee of 0.53%, this diversified fund is an attractive buy with a strong history of performance.

Franklin US Small Cap Equity I (LMSIX): 0.9% expense ratio and 0.7% management fee. LMSIX is a Small Cap Blend mutual fund, allowing investors a way to diversify their funds among various types of small-cap stocks. The fund is mainly invested in equities, has a long reputation of salutary performance, and has yearly returns of 9.52% over the last five years.

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.