Wells Fargo also put a $34 price target on the stock, which implies a 30% premium to its current price. The stock finished down 3.2% at $26.50 on Friday.
The average price target for Pinterest is $33.84, according to Bloomberg.
Wells Fargo analyst Brian Fitzgerald said he expected to see "continued revenue-growth runway" for the company.
"Alongside the top-line growth opportunity, we expect PINS to significantly expand margins, with EBITDA margin expanding from -5% in 2018 to 25%+ long term," the analyst said in Sept. 26 note.
"Yet while we're constructive on fundamentals, we view valuation as close to full at current levels and, as such, initiate coverage with a Market Perform rating."
The San Francisco company's stock is up about 38% from its IPO price of $19 in April.