Facebook's head of recruiting explains what it's like to interview there

Facebook is not only the best place to work in America - it's one of the most desirable employers in the world.

It has 13,000 employees across 64 offices around the globe, and it continues to scale its size and ambition.

Key to this growth is finding exceptionally talented employees who are also committed to Facebook's mission "to give people the power to share and make the world more open and connected."

Miranda Kalinowski, Facebook's global head of recruiting, explained to Business Insider what the tech powerhouse looks for and how the interview process works.

"We need to make sure that we're hiring people who are deeply invested in us, first and foremost," she said. "And we hire builders. So regardless of whether we're hiring an engineer or a finance analyst, they're going to be the people who like to build things."

Before applicants are hired, they'll typically go through four or five interviews that gauge their talent and cultural fit.

The first round is a phone interview with a recruiter, who assesses the candidate's professional experience and passion for the company.

If that goes well, the candidate will then have a "technical" phone interview with someone who already has the job the candidate is applying for. For example, an engineer will be interviewed by a fellow engineer rather than by a recruiter who knows nothing about programming.

Any of these non-recruiter employees selected to do interviews must first undergo intensive training to ensure they know what to look for.

The third interview takes place on site and includes an office tour, which features a demo of the Oculus virtual reality headset to take some of the pressure off the candidate and help them open up.

"It's very much a two-way street," Kalinowski said. "They can find out more about us, and we can find out more about them."

The remaining interviews are subject to the role and department. For example, an engineer may go through a coding interview, where an employee sees how quickly and accurately a candidate can write code on a whiteboard in response to a given situation.

All candidates are subject to hypothetical questions to test how they would respond on the job, as well as logic questions to test how they think - all of which ultimately test whether the person is right for Facebook.

Kalinowski's favorite interview question, which is also popular among other interviewers there, is: "On your very best day at work - the day you come home and think you have the best job in the world - what did you do?" The interviewer is taught to look for an answer that indicates candidates will be personally driven to stretch themselves at Facebook, since a high level of talent is a prerequisite in the highly competitive tech industry.

The candidates who get hired are the ones who demonstrate that they're just as excited as Facebook CEO Mark Zuckerberg is, Kalinowski said. "Anyone who listens to Mark will hear him say that we've still got 5 billion people to connect, so no one should be resting on their laurels. That sense of urgency and energy around it is infectious. "