Which Country Emits the Most CO2? When China Passed the US, and Where Japan Stands

Here are the questions people ask most, answered in order. Numbers are calculated from World Bank statistics (originally from the EU’s EDGAR research database). News reports, research analyses and government targets are kept apart from the data and carry sources.

• Who is first? China in 2024. It passed the United States in 2005.
• Where does Japan stand? 5th in total (2.6% of the world), and 25th of 186 per person.
• And per person? The top is the small country of Palau (82.8 tonnes). China is at 9.3 tonnes, 68% of the US figure.
• What about past emissions? Cumulatively, from 1751–2017, the United States leads with about 25% (Our World in Data).
• Has China started to cut? An analysis finds emissions flat or falling since March 2024, but in this dataset 2024 is still the highest year.

Who emits the most CO2 now? Top 10 (2024)

Top 10 CO2 emitters, 2024

Rank	Country	Emissions (million tonnes)	Share of world	Per person (tonnes)	Rank per person
1	China	13,125	34.6%	9.3	19
2	United States	4,632	12.2%	13.6	13
3	India	3,154	8.3%	2.2	99
4	Russia	2,009	5.3%	14.0	12
5	Japan	972	2.6%	7.8	25
6	Iran	829	2.2%	9.1	20
7	Indonesia	812	2.1%	2.9	85
8	Saudi Arabia	653	1.7%	18.5	8
9	South Korea	588	1.6%	11.4	15
10	Germany	580	1.5%	6.9	32

Shares are of the total across the 186 countries with data (37.9 billion tonnes). Rank per person is among 186 countries.

The top two make up 47% of the world. China alone emits about 1.7 times as much as the second and third countries, the United States and India, combined.

When did China pass the United States?

In this dataset China (6.2 billion tonnes) passed the United States (5.9 billion tonnes) in 2005. Before that, from 1970 to 2004, the United States was first every year. In 1970 the United States accounted for 30% of world emissions and China 6%. In 2024 it is 12% and 35%.

US emissions peaked in 2000 at 5.9 billion tonnes. In 2024 they are 4.6 billion tonnes, 22% lower. China, by contrast, emits 14.4 times as much as in 1970. India’s emissions rose 14.8-fold, passing Japan in 2006 and Russia in 2011 to take third place.

What about emissions per person?

China leads in total, but with a population of over 1.4 billion the per-person picture is different. In 2024, emissions per person were 13.6 tonnes in the United States, 9.3 in China, 7.8 in Japan and 2.2 in India.

China’s per-person figure passed Germany’s in 2019 and Japan’s in 2020. In 2024 it ranks 19th of 186, above Japan (25th). In 2007 reports put China’s per-person emissions at about a quarter of the US level (Nature news report). Today it is 68%.

The top of the per-person list is Palau (82.8 tonnes), followed by Qatar (47.3): Palau, Qatar, Bahrain, Kuwait, Brunei, all small countries. It is an entirely different cast from the ranking by total.

What if we add up all past emissions?

CO2 stays in the atmosphere for hundreds of years, so the running total matters as well as the yearly figure. According to Our World in Data, over 1751–2017 the United States emitted about 400 billion tonnes, about 25% of the world total, the most of any country. China is second, at about half the US total, and the EU about 22% (Our World in Data). The data in this article start in 1970, so the cumulative figures come from that source.

Where does Japan stand? Is it cutting?

Japan is 5th in total, in 1970 and in 2024. In 2024 it emitted 1.0 billion tonnes, 2.6% of the world, or 7.8 tonnes per person, 25th of 186. Japan’s emissions peaked in 2013 at 1.3 billion tonnes and are 27% lower in 2024.

The government’s targets, measured against fiscal 2013, are cuts of 46% by fiscal 2030, 60% by fiscal 2035 and 73% by fiscal 2040, and net zero by 2050 (Ministry of the Environment, in Japanese). These cover all greenhouse gases, not just CO2, and are counted by fiscal year, so they are not directly comparable with the CO2 statistics used here.

Has China started to cut emissions?

An analysis by the research group CREA, published by Carbon Brief on May 14, 2025, found China’s CO2 emissions flat or falling since March 2024, with January–March 2025 down 1.6% from a year earlier. It credits growth in solar, wind and nuclear power outpacing the rise in electricity demand. Some areas are still growing, such as coal-based chemicals (Carbon Brief).

In this dataset, China’s highest year is still 2024 (13.1 billion tonnes). Annual statistics and quarterly or monthly estimates differ in timing and method. Whether emissions have peaked will be settled by the numbers still to come.

How to read these numbers

• The series is a World Bank indicator, originally from the EU’s EDGAR database. It covers carbon dioxide only, excludes land-use change such as deforestation, and counts emissions inside each country’s borders.
• “World” here means the sum of the 186 countries with data. A few small countries have no value.
• Statistics that count only energy-related CO2, such as the International Energy Agency data used in Japanese government documents, give different numbers. The broad ranking is the same.
• Data: World Bank, updated 2026-10-08; retrieved by this site on November 5, 2026.

Summary

• In 2024, China emitted the most CO2 (13.1 billion tonnes, 35% of the world) and passed the United States in 2005.
• Japan is 5th. Its emissions peaked in 2013 and are 27% lower. Per person it is 25th of 186.
• Per person, China (9.3 tonnes) passed Japan (7.8) in 2020. The United States is at 13.6.
• The United States leads cumulatively. India passed Japan in 2006 and is third.