Every major fusion experimental facility

United States · Magnetic confinement (tokamak)

DIII-D

DIII-D National Fusion Facility

The largest US tokamak — a flexible workhorse for fusion plasma physics serving the US fusion program and ITER.

Operational · General Atomics · DOE

China · Magnetic confinement (superconducting tokamak)

EAST

Experimental Advanced Superconducting Tokamak

China's "artificial sun" — a superconducting tokamak setting world records for long-duration high-temperature plasma operation.

Operational · Hefei Institutes of Physical Science · CAS

France · Magnetic confinement (tokamak)

ITER

International Thermonuclear Experimental Reactor

The largest fusion experiment ever built — a $25B+ international project designed to demonstrate Q = 10 sustained burning plasma.

Under construction · ITER Organization

United Kingdom · Magnetic confinement (tokamak)

JET

Joint European Torus

For 40 years the world's largest tokamak — set fusion-energy records and validated ITER physics before shutdown in December 2023.

Decommissioned (2023) · EUROfusion · UKAEA

Japan · Magnetic confinement (tokamak)

JT-60SA

Japan Torus-60 Super Advanced

The world's largest operating tokamak — a joint Japan-EU device serving as a satellite to ITER.

Operational · QST · F4E

South Korea · Magnetic confinement (superconducting tokamak)

KSTAR

Korea Superconducting Tokamak Advanced Research

A superconducting tokamak that sustained 100 million K plasma for 48 seconds — a world record for ion temperature endurance.

Operational · Korea Institute of Fusion Energy

Japan · Magnetic confinement (stellarator/heliotron)

LHD

Large Helical Device

Japan's superconducting heliotron — for decades the largest stellarator-class device, pioneering steady-state magnetic confinement.

Operational · National Institute for Fusion Science

United Kingdom · Magnetic confinement (spherical tokamak)

MAST-U

Mega Amp Spherical Tokamak Upgrade

A spherical tokamak testing the Super-X divertor concept — critical for managing exhaust heat in compact fusion power plants.

Operational · UKAEA · Culham

United States · Inertial confinement (laser)

NIF

National Ignition Facility

The world's largest and most energetic laser, achieving the first laboratory fusion ignition in December 2022.

Operational · Lawrence Livermore National Laboratory

United States · Magnetic confinement (compact tokamak)

SPARC

Commonwealth Fusion's compact high-field tokamak designed to be the first device to achieve Q > 2 — and the prototype for the commercial ARC reactor.

Under construction · Commonwealth Fusion Systems · MIT PSFC

United States · Magnetic confinement (tokamak)

TFTR

Tokamak Fusion Test Reactor

The historic Princeton tokamak that first achieved deuterium-tritium fusion in the US and held the fusion power record for years.

Decommissioned (1997) · Princeton Plasma Physics Laboratory · DOE

Germany · Magnetic confinement (stellarator)

Wendelstein 7-X

The largest and most advanced stellarator ever built — proving that twisted magnetic geometry can confine plasma without disruptions.

Operational · Max-Planck-Institut für Plasmaphysik