The milestone comes more than five years after Google's shares initially hit $700, but then tumbled as the 2007 financial meltdown sparked global recession.
Its resurgent stock is an implicit endorsement of co-founder Larry Page, who replaced his managerial mentor Eric Schmidt as chief executive in April 2011.
Google's stock has risen by 36% since Mr Page took over.
The iPhone maker's market value has plunged by around $230bn, or 35%, since late September.
But it remains the most valuable US company with a market value of $432bn. Google now ranks third with a value of $266bn.
Tuesday trading saw Google stock climb 1.8% to close at $806.85.
Standard & Poor's Capital IQ analyst Scott Kessler said: "There are probably even going to be people talking whether Google's stock can get to $1,000.
"Never underestimate the excitement that can be caused by a rising stock market and a rising security."
More From Sky News