A penthouse at The Pacific in San Francisco has broken the city’s price record for the most expensive condo sold by square foot, Mansion Global has learned.

The four-bedroom, two-story unit spanning 4,048 square feet has sold for $15.875 million, according to property records. At $3,921 per square foot, the sale at the luxury new development, located on Webster Street in the ritzy neighborhood of Pacific Heights, sets a new condo price record for the City by the Bay, according to sales data from Redfin.

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Only a few single-family house sales have been more expensive by square foot, including the Goldman House in Presidio Heights, which sold to the tune of $4,289 per square foot, or $17.5 million in total, in 2012, according to property records.

The Pacific, a nine-story building by Handel Architects, is a former dental school converted into a luxury building with 76 units. The record-breaking sale is for one of four top-floor units, which developer Trumark Urban is selling with customizable floor plans, according to the developer.

"We can move bathrooms around, we can move stairs around," said Arden Hearing, managing director at Trumark Urban. "We are able to work with buyers to achieve their vision."

The Pacific is the only new condo construction in Pacific Heights and is marketing itself as an ultra-luxury alternative to the many single-family homes in the upscale neighborhood, Mr. Hearing said.

The building is more than 80% sold since sales launched last summer and has brought in over $200 million in revenue, Mr. Hearing said.

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This particular penthouse comes with a nearly 2,000-square-foot terrace and north- and west-facing views of the bay and the Golden Gate Bridge.

The buyer is listed in property records as venture capitalist Steven Merrill, who did not immediately respond to request for comment. The unit closed in January, records show.