When Nevada-based attorney Bernard Chao was evaluating how far to push a jury for compensatory damages to settle a lawsuit, he faced two options. On the one hand, he could pay $100,000 for a few hours’ work from jury consultants. On the other, he could pay $3,000 to conduct an online survey of a random group of people to ask how much would be appropriate. Chao went with the latter, provided by a Provo, Utah, upstart called Qualtrics (#128, The Unicorn List).

The legal industry is legendary for its massive amounts of paperwork. But law firms are beginning to look to the lowly online survey to save not just trees—after all, they didn’t seem terribly worried about conservation before—but also money and time.

It’s a realization at which many companies large and small have arrived. The online questionnaire is now a fixture in the corporate world, one data-driven tool among many to solicit targeted feedback from customers and employees. According to the Global Research Business Network, online surveys now account for more than a quarter of global market and social research revenues. At an estimated $10 billion, that’s more than telephone and face-to-face surveys combined. What’s more, the online quiz is now the primary means of research in many of the world’s top research markets.

For a law firm the calculation is simple: An online survey can speed up the process for a lawyer to evaluate a jury, better predict a possible trial outcome, and dramatically cut research costs along the way.

“I am spending $3,000 to get better results than the service I am paying $100,000 for,” says Chao, who also teaches law at the University of Denver. “It’s a no-brainer.”

It didn’t use to be this way. The legal profession was once dominated by jury consultants, powerful agents who would assemble a test jury that would serve as a focus group to identify weaknesses in a legal argument and reflect how a real jury might react. Feedback from test jurors might emerge from interviews or paper surveys, Chao says. The test jury would typically span no more than 30 people. Meanwhile, an online survey could reach 400 people—a sample size that may better represent the greater population.

Ryan Smith, CEO and founder of QualtricsPhotograph by James Winegar

Companies like Qualtrics, SurveyMonkey (#56, The Unicorn List), SurveyGizmo, and QuestionPro know that businesses are willing to pay for better insights. So do their investors. Qualtrics and SurveyMonkey, for example, have raised hundreds of millions of dollars in venture capital (at billion-dollar valuations) to blossom into full-service business-intelligence firms rather than remain solely web-survey providers. With sophisticated algorithms in development and talented data scientists on hand, they’re positioning themselves no differently than other Silicon Valley software startups that seek corporate customers.

“Instead of waiting six months for results, you can have answers within hours,” says Jon Cohen, former head of polling at the Washington Post who now leads research at SurveyMonkey. It’s also the reason his colleague Eleanor Lacey, SurveyMonkey’s general counsel, uses the company’s tools to approve board motions, shortening a process that once required calling each director for a verbal approval.

Yet the legal applications can be fascinating. Qualtrics says one of its customers, a criminal-law firm in Atlanta, used its surveys to test for racism in potential jury members. (Their use is subject to judicial discretion.) The firm’s attorneys asked each possible juror to take a survey with a randomized image of a person of African, Asian, or European descent. Then the lawyers asked the candidates questions about the images. Their goal, says Qualtrics: Weed out implicit bias in a potential juror.

A different law firm used Qualtrics’s surveys to prepare potential jury members for legal jargon—“manslaughter” or “second degree”—likely to be used in a case. In this example, the results helped attorneys remove or replace language in their arguments.

“Decisions that used to be based on intuition can now be based on data,” Cohen says.

Not every law firm is onboard with the technology. Some share concerns that online surveys put sensitive information at risk. (Qualtrics and SurveyMonkey say they do not sell or share specific user data except in cooperation with law enforcement.) The sentiment matches that of the general population: According to a recent Pew Research Center report, confidence in the security of online communications channels is waning, particularly for online tools such as surveys.

The benefits are worth the risk, Chao says: “It’s like playing Moneyball with the law.”

Expect surveys to appear in more courtrooms around the country—and not just in the jury box either. The State Bar of California, for example, tapped SurveyMonkey to gather data on nominees for potential judicial appointments. And with so many smartphones in the wild—60% of responses to Qualtrics surveys came from them, the company says—it’s not hard to imagine a world where court cases could be decided from the comfort of a juror’s home.

Wishful thinking, perhaps. But the impact on the legal profession is not to be underestimated. Says Ryan Smith, CEO and co-founder of Qualtrics: “It’s one more example of how software is changing every industry.”

To see The Unicorn List, visit fortune.com/unicorns.

A version of this article appears in the September 15, 2015 issue of Fortune magazine with the headline “Do lawyers like surveys?”