While the proven Zacks Rank places an emphasis on earnings estimates and estimate revisions to find strong stocks, we also know that investors tend to develop their own individual strategies. With this in mind, we are always looking at value, growth, and momentum trends to discover great companies.Of these, perhaps no stock market trend is more popular than value investing, which is a strategy that has proven to be successful in all sorts of market environments. Value investors use tried-and-true metrics and fundamental analysis to find companies that they believe are undervalued at their current share price levels.Luckily, Zacks has developed its own Style Scores system in an effort to find stocks with specific traits. Value investors will be interested in the system's "Value" category. Stocks with both "A" grades in the Value category and high Zacks Ranks are among the strongest value stocks on the market right now.Sprouts Farmers (SFM) is a stock many investors are watching right now. SFM is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock has a Forward P/E ratio of 13.97. This compares to its industry's average Forward P/E of 16.07. Over the past year, SFM's Forward P/E has been as high as 17.67 and as low as 10.30, with a median of 12.75.Investors will also notice that SFM has a PEG ratio of 1.50. This popular figure is similar to the widely-used P/E ratio, but the PEG ratio also considers a company's expected EPS growth rate. SFM's industry currently sports an average PEG of 1.77. Over the past 52 weeks, SFM's PEG has been as high as 4.78 and as low as 1.12, with a median of 1.37.Finally, we should also recognize that SFM has a P/CF ratio of 6.16. This figure highlights a company's operating cash flow and can be used to find firms that are undervalued when considering their impressive cash outlook. This stock's P/CF looks attractive against its industry's average P/CF of 8.44. Over the past year, SFM's P/CF has been as high as 7.93 and as low as 4.48, with a median of 5.75.These are only a few of the key metrics included in Sprouts Farmers's strong Value grade, but they help show that the stock is likely undervalued right now. When factoring in the strength of its earnings outlook, SFM looks like an impressive value stock at the moment.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Sprouts Farmers Market, Inc. (SFM): Free Stock Analysis Report To read this article on Zacks.com click here.