The short answer: Earth's atmosphere weighs about 5.15 x 10^18 kilograms (roughly 5.15 quadrillion metric tons, or about 1.1 x 10^19 pounds). Scientists estimate this from surface pressure, gravity, and the planet's total area.
Atmosphere weight by type
The atmosphere cannot be weighed directly, so its mass is calculated from the pressure it exerts at the surface. Every square meter at sea level supports about 10.3 metric tons of air column.
| Atmospheric layer (example) | Approximate share of total mass |
|---|---|
| Troposphere (0-12 km) | about 75-80 percent |
| Stratosphere (12-50 km) | about 19 percent |
| Mesosphere (50-85 km) | under 1 percent |
| Thermosphere and exosphere | a tiny fraction |
What affects atmosphere weight
- Surface pressure. The weight of the air column per square meter is the key input.
- Earth's area. Multiplying pressure by the planet's total area gives the mass.
- Gravity. The strength of gravity converts pressure into a mass figure.
- Water vapor. Atmospheric moisture adds a small, variable amount.
- Altitude profile. Most mass concentrates in the lowest layers.
- Pressure variation. A global average accounts for differences across the planet.
How atmosphere weight compares
The atmosphere weighs about a millionth of the Earth itself, yet each square meter of ground supports an air column weighing roughly as much as two cars stacked above it.
Frequently asked questions
How can the atmosphere be weighed if it can't be put on a scale?
Scientists use surface air pressure, which equals the weight of the air column above each spot, then multiply by Earth's area to get the total mass.
Why don't we feel the atmosphere's weight?
Air pressure pushes on us equally from all directions and our bodies are pressurized to match, so we never sense the roughly 10 tons pressing on each square meter.
Where is most of the atmosphere's mass?
About three-quarters of it lies in the troposphere, the lowest layer, within roughly 12 kilometers of the surface.
