But individuals who frequent them say scams are pervasive. Match.com, for instance, includes a disclaimer at the bottom of every onsite email between members, warning not to send money or provide credit card information to anyone you've met on the site.
"I probably hear from five scammers a night," says Marko Budgyk, a Los Angeles financier who has frequented several online dating sites over the past 10 years.
Sh'reen Morrison had been on an online dating site for only a few weeks before she realized that something was seriously wrong with the man who had been actively pursuing her by text message and email.
They'd hit it off right away, and he said he lived just outside of Phoenix, which seemed relatively proximate to a woman in remote Yuma, Ariz.
Where do the scammers get photos of themselves in these exotic locations and with these costly products? They troll other sites and steal other people's photos. Many are operating out of foreign countries, despite profiles saying they live nearby. When she declined, the messages got more desperate.
Budgyk knows this from experience: A Nigerian scammer lifted photos from Budgyk's profile. Their photographs are also likely of someone else, and that would be tough to explain in person. He sent heart-wrenching photos of a young girl, who appeared to be his daughter's age, hooked to a raft of medical monitors.
There are no statistics saying just how common scammers are on dating sites.
"After a while, it becomes really easy to spot them." Here are six red flags to help detect and sidestep romance scams.