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

Janus Henderson Enterprise S (JGRTX) has a 1.16% expense ratio and 0.64% management fee. JGRTX is a Mid Cap Growth mutual fund. These funds aim to target companies with a market capitalization between $2 billion and $10 billion that are also expected to exhibit more extensive growth opportunities for investors than their peers. With yearly returns of 11.66% over the last five years, this fund clearly wins.

Fidelity Equity Dividend Income (FEQTX Quick QuoteFEQTX - Free Report) : 0.55% expense ratio and 0.53% management fee. FEQTX is a part of the Large Cap Value category, and invests in equities with a market capitalization of $10 billion or more, but whose share prices do not reflect their intrinsic value. With yearly returns of 13.68% over the last five years, FEQTX is an effectively diversified fund with a long reputation of solidly positive performance.

T. Rowe Price Institutional Large Cap Growth (TRLGX). Expense ratio: 0.55%. Management fee: 0.54%. Five year annual return: 15.67%. TRLGX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers.

These examples highlight the fact that there are some astonishingly good mutual funds out there. If your advisor has you in the good ones, bravo! If not, you may need to have a talk.