Kalanick was born on August 6, 1976 and grew up in Northridge, California. Kalanick's parents are Bonnie Renée Horowitz Kalanick (née Bloom) (died 2017) and Donald Edward Kalanick. Bonnie, who was Jewish, worked in Retail advertising for the Los Angeles Daily News. Donald, from a Slovakian-Austrian Catholic family whose grandparents emigrated to the United States, was a civil Engineer for the city of Los Angeles. Kalanick has two half-sisters, one of whom is Actress Allisyn Ashley Arm's mother Anji, and a brother, Cory, who is a firefighter.

In 1998, Kalanick, along with Michael Todd and Vince Busam, dropped out of UCLA to help Dan Rodrigues found Scour Inc., a multimedia search engine, and Scour Exchange, a peer-to-peer file sharing Service. In 2000, the Motion Picture Association of America (MPAA), the Recording Industry Association of America (RIAA), and the National Music Publishers Association (NMPA) brought a $250 billion lawsuit against Scour, alleging copyright infringement. In September 2000, Scour filed for bankruptcy to protect itself from the lawsuit.

Kalanick has an archived blog, Swooshing, where he shares struggles during this time. This included living over 3 years without a salary, moving into his parents' house in 2001 (which he told the Failcon 2011 audience and commented that he "wasn't getting ladies. It sucked."), owing "$110,000 to the IRS in un-withheld income taxes, which is a white-collar crime that pierces the corporate shell, and it doesn't matter whether you knew or not. If you're an officer of the company you're going to jail," witnessing "all but one of the company's engineers" leaving (who eventually also departed), and moving to Thailand as a cost-saving measure. Kalanick committed tax fraud and perjury during the IRS investigation, blaming his partner Michael Todd, but was never prosecuted. In 2007 Akamai Technologies acquired the company for $19 million.

In 2009, Kalanick joined Garrett Camp and gives him "credit for the original idea" of Uber. Camp, co-founder of StumbleUpon, spent $800 hiring a private driver with friends and had been mulling over ways to decrease the cost of black car services (meaning, taxis that are dispatched by a central Service rather than hailed directly on the street) ever since. He realized that sharing the cost with people could make it affordable, and his idea morphed into Uber. "Garrett is the guy who invented that shit", Kalanick said at an early Uber event in San Francisco. The first prototype was built by Camp, and his friends, Oscar Salazar and Conrad Whelan, with Kalanick being brought on as a "mega advisor" to the company. In October 2010, Kalanick succeeded Ryan Graves as CEO, who had held the position for ten months.

Kalanick is ranked 115th on the Forbes 400 list of richest Americans, with a net worth of $4.8 billion.

From 2014–2016, Kalanick dated Gabi Holzwarth.

Despite CTO Thuan Pham's 2016 internal email to employees commenting, "I will not even utter the name of this deplorable person because I do not accept him as my leader" on the election of U.S. President Donald Trump, which was widely circulated and published by the media, in December 2016, it was announced that Kalanick joined other CEOs, including Tesla CEO Elon Musk, J P Morgan CEO Jamie Dimon, General Motors CEO Mary Barra, Disney CEO Bob Iger, Walmart CEO Doug McMillon, and former General Electric CEO Jack Welch, as an economic advisor on Trump's Strategy and Policy Forum, organized by Blackstone's Stephen Schwarzman. Kalanick vocally opposed President Trump's executive order banning travel from select countries and believed that remaining on Trump's advisory council would provide him with the opportunity to directly address his concerns with the President and advocate for immigrants. In an Uber blog post, Kalanick stated that he wanted to use his position on the council to "give citizens a voice, a seat at the table." However, after continued pressure, Kalanick announced in an email to Uber employees that he would step down from the council.

On August 10, 2017, Axios reported that Benchmark is suing Kalanick for "fraud, breach of contract and breach of fiduciary duty." The suit is based on Uber's decision to expand the number of board seats, with Benchmark arguing the decision is invalid due to withholding of material information prior to the vote. The lawsuit was very controversial in Silicon Valley because of the relationship between the founder and the investor. The court ruled in the favor of Kalanick to move the case to arbitration on August 30. In response to the court ruling Kalanick released a public statement:

On March 7, 2018, Travis announced that he would start a venture fund, 10100 (pronounced 'ten-one-hundred') focused on job growth via his Twitter account. The fund is likely named after the address of his childhood home. The fund is going to tackle large scale employment opportunities by investing in e-commerce, innovation and real estate in emerging markets like China and India.