Love at First Byte: The Secret Science of Online Dating 9 p.m., CNBC
CNBC isn’t necessarily known as the most romantic network. But if you’ve ever clicked on an online dating website to see if you might click with someone in the real world, or wondered how the sites make their matches, you might want to check out this special. “Today’’ show correspondent Amy Robach (pictured) digs into the inner workings of all the major online yentas (including Match.com and eHarmony), the niche sites, and has chats with a good old-fashioned matchmaker and several online daters to see how the algorithms and psychology add up to love and big business.
I Just Want My Pants Back 11 p.m., MTV
This new series about a quartet of cool-but-confused young Brooklynites pulled solid ratings for the former music network in its debut last week. Tonight, Jason looks to network for a new job at a party thrown by James Franco. Considering how many jobs Franco has, maybe he can just lend him one.
The Vampire Diaries 8 p.m., Channel 56
Grey’s Anatomy 9 p.m., Channel 5
Valentine’s Day at Seattle Grace. Love, exciting and toxic.
Inside Comedy 11 p.m., Showtime
Co-executive producer Steve Carell sits down and yuks it up.