What Is OPEC — and Why Does It Move Oil Prices?

OPEC is a 12-member cartel that coordinates oil production to influence prices — its members pumped about 30.0 Mb/d of crude in 2025. With the OPEC+ alliance (adding Russia and others), the group steers roughly half of world supply. Here's how it works, who's in it, and its live production figures.

OPEC Member Production (EIA, 2025)

Mb/d crude incl. condensate

#	Country	Mb/d
1	Saudi Arabia	9.56
2	Iraq	4.39
3	Iran	4.05
4	United Arab Emirates	3.77
5	Kuwait	2.58
6	Nigeria	1.61
7	Libya	1.36
8	Algeria	1.14
9	Venezuela	0.97
10	Congo	0.24
11	Gabon	0.24
12	Equatorial Guinea	0.08

Full detail with shares on the OPEC production page; world context on world production & consumption.

How the Cartel Actually Works

The mechanics

Ministerial meetings (usually in Vienna or by video) set group and per-country production quotas, announced as barrels-per-day targets.
Voluntary cuts on top of quotas have become the recent tool of choice — led by Saudi Arabia, whose spare capacity makes it the swing producer.
Compliance is the perennial issue: members quietly overproduce, tracked monthly by secondary sources in OPEC\'s own MOMR report.

The limits of its power

US shale responds to high prices within months, capping how far cuts can push prices before losing market share.
Price wars — 1986, 2014–16, March 2020 — happen when the group opens the taps to punish rivals or each other.
Demand is beyond its control: recessions and efficiency gains have repeatedly overwhelmed supply management.

OPEC FAQ

What is OPEC?

The Organization of the Petroleum Exporting Countries is a cartel of 12 oil-producing nations, founded in 1960 and headquartered in Vienna, that coordinates production levels to influence prices. Together its members produced about 30.0 million barrels per day of crude in 2025 — roughly a third of world supply. Saudi Arabia is the de facto leader with the largest output and spare capacity.

What is the difference between OPEC and OPEC+?

OPEC+ is the wider alliance formed in 2016 that adds about 10 non-members — most importantly Russia, plus Kazakhstan, Mexico, Oman and others — to OPEC's coordination. Together OPEC+ controls roughly half of world production, which is why its quota decisions move prices more than OPEC alone ever could recently.

How does OPEC control oil prices?

By setting production quotas. Cutting output tightens supply and supports prices; raising it does the reverse. The tool works best when members comply and demand is stable — history is full of quota-cheating, price wars (1986, 2014, 2020) and periods when US shale undercut the cartel's pricing power.

Which countries are in OPEC?

Saudi Arabia, Iraq, Iran, the UAE, Kuwait, Nigeria, Libya, Algeria, Venezuela, Congo, Equatorial Guinea and Gabon. Notable departures: Qatar left in 2019, Ecuador in 2020, and Angola in 2024. The US, Russia, Canada, China and Brazil — five of the biggest producers — have never been members.