What gas do human and animals breathe out?

We breath in air (left), breath out (right) which is approx;

Nitrogen 79% -----------------------Nitrogen 79%

Oxygen 20% -------------------------Oxygen 16%

Argon 1%--------------------------------- Argon 1%

Carbon dioxide 0.0384% ---carbon dioxide 4%

We breath out air with a higher level of carbon dioxide and a lower level of oxygen; breathing also results in loss of water from the body, exhaled air has a relative humidity of 100% (with trace's of methanol and other organic compounds generated inside the body).

humans breathe in oxygen and breathe out carbon dioxide
Cabon dioxide