A frenzy has hit the market for newly listed tech stocks.

Last week, searing demand sent DoorDash Inc.'s stock up 86% in its trading debut Wednesday, while Airbnb Inc.'s shares more than doubled in their debut a day later.

Airbnb Chief Executive Brian Chesky was at a loss for words in a Bloomberg TV appearance when he was told of the company's opening share price, while multiple investors in the two blistering offerings said they were puzzled by the extraordinary enthusiasm in the market.