A quarter of Venmo users are currently using PayPal's millennial-friendly payments app in a way that the financial technology company can monetize, PayPal Chief Financial Officer John Rainey told CNBC on Friday.

"If we look at the most recent quarter, roughly one in four Venmo customers are using Venmo in a way today that we're able to monetize," Rainey said in an exclusive interview with "Mad Money" host Jim Cramer.

"That could be with using Venmo to shop online, it could be using our physical card in a store, or it could be using the instant cash withdrawal so they can transfer funds immediately into their bank account," the CFO continued.

Speaking after PayPal's strong earnings report sent shares of the payments giant up more than 9 percent in Friday's trading session, Rainey reiterated CEO Dan Schulman's comments about Venmo reaching a "tipping point."

"It's a bit of an inflection point for us," Rainey told Cramer, whose charitable trust owns shares of PayPal. "We saw growth ... of almost 80 percent in terms of total volume for Venmo in the quarter. That's the second quarter in a row that we've grown at that rate, and so we're just really excited about what we're seeing with this part of our platform."

While Venmo was a key driver for PayPal this quarter, it wasn't the company's only win: the fintech player added 9.1 million net new active users to its platform, an all-time record, announced an expanded partnership with American Express and struck a new agreement with Walmart to offer deposit and withdrawal services at its stores.

Rainey said the partnerships would be instrumental to drawing even more customers to PayPal's increasingly "relevant" platform, which now boasts over a quarter of a billion users.

Moreover, PayPal is still focused on the roughly two billion people around the world who don't have access to financial services that many people "take for granted," like banking or checking accounts, he said.

"Financial inclusion is part of our mission," he told Cramer. "The key element of those two billion people is that roughly 70 percent of them have a mobile device. And this is where our value proposition really shines, where we can put all of the power of mobile commerce in the palm of their hand."

That, paired with the almost "viral" popularity of the Venmo app, sets PayPal apart from traditional financial services companies or even newer fintech competitors, Rainey said.

"There are very few companies, Jim, that I would put into the same category as us," the CFO said. "We're a high-growth company, but we also generate a tremendous amount of free cash flow for a growth company like ours."