Amazon has become the second company listed in the US to achieve a market value of $1trn (£779.3bn).
Its stock surged during morning trading on the Nasdaq, reaching the milestone when its share price hit $2,050.50 per share.
It began the day needing just over $18bn worth of net value to reach $1trn - a month after Apple won the race to be the first company with such a market capitalisation.
It crossed the line at 16:40 BST before falling back slightly.
US tech stocks have largely enjoyed years of gains as stock markets hit record levels - with a few wobbles along the way.
Amazon, founded by its chief executive Jeff Bezos, started life in 1994 as a bookseller before expanding to become the world's largest internet retailer.
Investors were for years frustrated by profits being ploughed back into the funding of Amazon's growth.
But the widening of its horizons mean the company's interests now also include cloud computing, artificial intelligence and the streaming of entertainment.
In the past quarter, Amazon posted record profits of $2.5bn while its share price growth - up 75% in the year to date - has helped propel Mr Bezos to the top spot in the Forbes billionaire list with a paper wealth of $112bn at last count.