Jim Cramer on Friday recommended investors buy shares of Splunk at current levels, but only on a speculative basis, because he thinks the data analytics software maker could be a "big data game changer."

Splunk's services allow clients to index and search data stored in Hadoop, the open-source software widely used in big data analysis. Its business intelligence tools gather and process what's known as machine data, meaning the data gathered by all of the systems running in data centers. Previously, companies weren't doing much machine data because it was too big and too cumbersome to interpret.

"Splunk's software platform takes this machine data and makes it accessible, usable, and most of all, valuable, to their clients," Cramer said. "This the heart of the big data theme: you can use this information to diagnose service problems, detect security threats, assess the health of your remote equipment, catch fraudulent behavior, and demonstrate compliance to your regulators, among many other applications."

There's just one problem, though, Cramer continued. Splunk's stock is very expensive. It has doubled since the beginning of the year and has posted a gain of around 250 percent since its initial public offering in 2012. The stock currently trades at 12 times sales and though the company is not yet profitable, Cramer thinks it should move into the black next year.

Still, Cramer thinks Splunk is worth speculating on. He recommends investors start a small position at current levels, and then wait for a pullback before buying more.

Call Cramer: 1-800-743-CNBC

Questions for Cramer? madmoney@cnbc.com

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