83,000,000 t183,000,000,000 lb
All the ants on Earth weigh roughly 83 million tonnes (about 183 billion lb) alive. That is our estimate from a 2022 study that counted about 20 quadrillion ants holding 12 million tonnes of carbon, about 20% of humanity’s biomass. Taking 20% of the 415 million tonnes all humans weigh gives the number used here.
| Every human on EarthFor comparison: 8.3 billion people at 50 kg | 415,000,000 t915,000,000,000 lb |
|---|---|
| All ants, living weightThe figure on this page: 20% of humanity | 83,000,000 t183,000,000,000 lb |
| All ants, from the weight of one ant20 quadrillion ants at about 3.8 mg each | 76,000,000 t168,000,000,000 lb |
| All ants, dried20 quadrillion ants at 1.24 mg dry weight each | 24,800,000 t54,700,000,000 lb |
| All ants, carbon onlySchultheiss et al. (2022), best estimate | 12,300,000 t27,100,000,000 lb |
Nobody can weigh all the ants, so the figure is an estimate in two steps. In 2022, Schultheiss and colleagues published the first count built from field data in PNAS. They put the number of ants on Earth at about 20 quadrillion (2 × 10¹⁶) and their total biomass at 12.3 million tonnes of dry carbon, which they say is about 20% of human biomass, measured the same way.
Scientists compare living things by their carbon because it ignores water, which varies a lot between species. To get a weight you could put on a scale, we applied that 20% to the living weight of all humans. Our page on every human on Earth puts that at about 415 million tonnes, so the ants come to about 83 million tonnes.
A second route gives nearly the same answer. The study assumed an average worker ant weighs 1.24 mg dried. Fire ant workers, measured in a 2020 study in Insects, are about 68% water, so a 1.24 mg dry ant would weigh about 3.8 mg alive. Twenty quadrillion of those come to about 76 million tonnes, by our maths.
The team combined 489 studies from every continent and major habitat where ants live, covering 26,800 square metres of sifted leaf litter and more than 2 million trap-days of pitfall sampling. From this they estimated about 3 quadrillion ants foraging on the ground. Adding ants in tree canopies and the many workers that never leave the nest brought the total to 19.8 quadrillion, give or take 5 quadrillion.
That is about 2.5 million ants for every person alive, according to a PNAS commentary on the study by Tom Fayle and Petr Klimes. The ants are far from evenly spread: 61% of ground-dwelling ants live in tropical moist forests and tropical savannas, which make up only about 38% of the land ants inhabit.
The authors call their figures conservative. Boreal forests, mangroves and everything underground had too little data to include, and the count leaves out eggs, larvae, queens and males.
It is a popular claim, but the new study says no. Earlier estimates ranged widely: Bert Hölldobler and E. O. Wilson’s figures worked out to 2.5 to 25 million tonnes of carbon, while a 2020 estimate by Tuma and colleagues reached about 70 million tonnes, close to the 60 million tonnes of carbon in all humans. The 2022 count, based on far more data, lands at about a fifth of humanity.
Ants are still heavyweights among wild animals. At 12.3 million tonnes of carbon, they outweigh all wild birds and wild mammals put together.
Ants vary enormously in size. For their estimate, Schultheiss and colleagues used body mass measurements from 534 species, whose dried workers range from 0.004 mg to 57 mg, a difference of more than 10,000 times.
Even within one species, workers differ. In the 2020 study of four fire ant species, small workers weighed 0.59 to 1.18 mg and large ones 3.08 to 5.26 mg alive.
About 83 million tonnes alive, by our estimate, or roughly 12 million tonnes if you count only their carbon. That is about a fifth of what all humans weigh.
About 20 quadrillion, or 20,000,000,000,000,000, according to a 2022 study in PNAS. The authors consider that a conservative figure.
No. The 2022 study puts all ants at about 20% of human biomass. Older estimates suggested the two might be equal, but they rested on much less data.
About 2.5 million ants for every person alive.
Usually a few milligrams. Fire ant workers weigh about 0.6 to 5 mg alive, and dried workers across 534 species range from 0.004 mg to 57 mg, with an average of 1.24 mg used for the global estimate.
Last checked October 4, 2026.
