The U.S. housing sector is recovering after years of dragging down the broader economy. U.S. home sales hit a three-year high in February and prices jumped, data from the National Association of Realtors showed.
Zillow now expects revenue of $178 million to $182 million for the full year, up from its earlier forecast of $165 million to $170 million.
Analysts on average were expecting $172.3 million, according to Thomson Reuters.
Zillow said average monthly unique users to its website increased 47 percent to 46.7 million in the first quarter.
The company, which also provides estimated home values called "Zestimates," gets most of its revenue from subscriptions by real-estate agents who list their properties on its site.
Zillow got nearly three-fourths of its 2012 revenue of $116.9 million from its marketplace business, which includes subscriptions by agents and advertising by mortgage lenders.
The company posted a net loss of $3.7 million, or 11 cents per share, in the first quarter, compared with a net profit of $1.7 million, or 6 cents per share, a year earlier.
Revenue rose 71 percent to $39 million from $22.8 million in the year-earlier period.
Analysts on average had expected a loss of 3 cents per share on revenue of $37.4 million, according to a consensus estimate from Thomson Reuters.
Premier agents, or paying subscribers, rose 83 percent to a total of 34,030 in the quarter.
Revenue from marketplace rose 87 percent to $31 million.
The company competes with Move, owner of sites such as Realtor.com, and Trulia.
Trulia last week reported better-than-expected first-quarter revenue as traffic rose from mobile devices and it forecast current-quarter revenue comfortably above analysts' estimates.
Zillow shares closed at $62.94 in after-hours trading on the Nasdaq on Tuesday. They have gained 67 percent in the past three months.
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