Ann Arbor-based global chain Domino’s Pizza has surpassed $1 billion in online sales, officials announced this morning.

To mark the occasion, Domino’s is offering free Chocolate Lava Crunch Cakes to customers who enter the promotional code “HUG” with an online order on Valentine’s Day.

“We are thrilled with how our innovative online ordering system has been doing since day one, and we owe that success to our customers,” Domino’s Chief Marketing Officer Russell Weiner said in a news release.

“It’s clear after $1 billion in sales online that consumers are taking full advantage of the convenience and efficiency of our online ordering process, and we want to thank them for that.”

Online sales represent about 20 percent of Domino’s orders. Domino’s said last year that it had surpassed competitors Pizza Hut and Papa John’s as the biggest online pizza ordering system in the country. 

Domino’s is reshaping the digital structure of its online ordering system and building its own internal information technology staff to handle the site, instead of contracting with an outside firm

“We’re offering Silicon Valley jobs in Ann Arbor,” Christopher McGlothlin, Domino’s chief information officer, told AnnArbor.com in December.

Domino’s (NYSE: DPZ) has about $1.37 billion in annual revenue at some 8,700 stores with about 10,500 full-time workers, including about 500 at its headquarters in Ann Arbor Township.

Contact AnnArbor.com’s Nathan Bomey at (734) 623-2587 or nathanbomey@annarbor.com. You can also follow him on Twitter.