SAN FRANCISCO — Box can now integrate with the desktop version of Microsoft’s Office 365 software, Box cofounder and chief executive Aaron Levie announced today.

It’s now available in beta.

More than 240,000 businesses use Box now — that comes out to more than 27 million users. And 99 percent of the Fortune 500 use Box, according to the latest statistics. Analyst R “Ray” Wang tweeted out today that only 8 percent of the “base” pays for Box, though.