Microsoft hit the trillion-dollar value mark on Thursday for the first time, becoming the third technology giant to reach the symbolic milestone.
Shares in Microsoft rallied some five per cent to US$130.59 (NZ$196) in early Wall Street trade after a robust earnings report a day earlier.
That gave Microsoft a market capitalisation of just over US$1 trillion (NZ$1.5 trillion), before dipping back slightly.
At its current levels, Microsoft is the world's most valuable company, ahead of Apple and Amazon, which last year topped $1 trillion before slipping back.
On Wednesday, Microsoft said profits in the quarter to March 31 rose 19 per cent to US$8.8 billion (NZ$16.5 billion) on revenues of US$30.8 billion (NZ$46 billion), an increase of 14 per cent from the same period a year earlier.