A report has said that mankind will have used up its allowance of natural resources such as water, soil and clean air for all of 2019 by today.
The study by the Global Footprint Network, a California-based environmental group, says the so-called Earth Overshoot Day has moved up by two months over the past 20 years and that this year's date is the earliest ever.
The equivalent of 1.75 planets would be required to produce enough to meet humanity's needs at current consumption rates.
The group, whose headquarters is in Oakland, said: "Earth Overshoot Day falling on 29 July means that humanity is currently using nature 1.75 times faster than our planet's ecosystems can regenerate. This is akin to using 1.75 Earths.
"The costs of this global ecological overspending are becoming increasingly evident in the form of deforestation, soil erosion, biodiversity loss, or the build-up of carbon dioxide in the atmosphere.
"The latter leads to climate change and more frequent extreme weather events."
Calculated since 1986, the grim milestone has arrived earlier each year.
In 1993, it fell on 21 October, in 2003 on 22 September, and in 2017 on 2 August.
Mathis Wackernagel, founder of Global Footprint Network, said: "We have only got one Earth - this is the ultimately defining context for human existence. We can't use 1.75 (Earths) without destructive consequences."
Maria Carolina Schmidt Zaldivar, Chile's environment minister and chair of the Climate COP25 scheduled this December in Santiago, said a major cause of the date falling earlier and earlier was growing amounts of CO2 emissions.
She said: "The importance of decisive action is becoming ever more evident."