What is the percentage of carbon dioxide in the atmosphere?

The earth's atmosphere contains about 0.03% carbon dioxide.

Earth's atmosphere is a mixture of gases. Nitrogen is about 78% of the total gases in the earth’s atmosphere. Oxygen is the second most abundant gas. Oxygen is needed for survival, as living organisms required oxygen for breathing. It occupies almost 21% of the total gases in the atmosphere. Argon, carbon dioxide and many other gases form the remaining 1%. Carbon occupies about 0.03% of the earth’s atmosphere. Nowadays, the level of carbon-dioxide increases due to the burning of fossil fuels, deforestation, etc.