Director, Nuclear Information Project
Hans Kristensen
Status of Worldwide Nuclear Arsenals,
Nuclear Policy and strategy, De-alerting,
Nuclear Weapons

email: hkristensen @ fas.org
twitter: @nukestrat

Hans M. Kristensen is Director of the Nuclear Information Project at the Federation of American Scientists where he provides the public with analysis and background information about the status of nuclear forces and the role of nuclear weapons. He specializes in using open sources and the Freedom of Information Act (FOIA) in his research to increase transparency of nuclear arsenals and is a frequent consultant to and is widely referenced in the news media on the role and status of nuclear weapons.

His collaboration with researchers at the Natural Resources Defense Council in 2010 resulted in an estimate of the size of the U.S. nuclear weapons stockpile that was only 13 weapons off the actual number declassified by the U.S. government. Likewise, his estimates of Russian and Chinese nuclear stockpiles have been close to U.S. government numbers.

Kristensen is co-author of the Nuclear Notebook column in the Bulletin of the Atomic Scientists and the World Nuclear Forces overview in the SIPRI Yearbook, which he has co-authored since 2001. The Nuclear Notebook is, according to the publisher, “widely regarded as the most accurate source of information on nuclear weapons and weapons facilities available to the public.” Past Nuclear Notebook columns can be found here. A full listing of Kristensen’s publications can be found here.

Between 2002 and 2005, Kristensen was a consultant to the nuclear program at the Natural Resources Defense Council in Washington, D.C, where he researched and published on nuclear weapons issues. Between 1998 and 2002, Kristensen directed the Nuclear Strategy Project at the Nautilus Institute in Berkeley, CA, and he was a Special Advisor to the Danish Ministry of Defense in 1997-1998 as a member of the Danish Defense Commission. He was a Senior Researcher with the Nuclear Information Unit of Greenpeace International in Washington D.C from 1991 to 1996, prior to which he coordinated the Greenpeace Nuclear Free Seas Campaign in Denmark, Norway, Finland and Sweden.

publications
Nuclear Weapons
Blog
Chinese Nuclear Forces, 2024: A “Significant Expansion”

Analyzing and estimating China’s nuclear forces is challenging, particularly given the relative lack of state-originating data and the tight control of messaging surrounding the country’s nuclear arsenal and doctrine.

01.16.24 | 4 min read
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Nuclear Weapons
Blog
New Nuclear Bomb Training At Dutch Air Base

The Dutch air base at Volkel appears to have started integration training with the new U.S. B61-12 guided nuclear gravity bomb in 2021, even before the bomb went into full-scale production and entered the U.S. stockpile in 2022.

12.13.23 | 3 min read
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Nuclear Weapons
Report
Nuclear Notebook: Nuclear Weapons Sharing, 2023

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans […]

11.17.23 | 1 min read
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Nuclear Weapons
Blog
Biden Administration Decides To Build A New Nuclear Bomb to Get Rid Of An Old Bomb

[UPDATED] The Biden administration has decided to add a new nuclear gravity bomb to the US arsenal. The bomb will be known as the B61-13.

10.27.23 | 8 min read
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Nuclear Weapons
Blog
Upgrade Underway for Russian Silos to Receive New Sarmat ICBM

New satellite imagery shows that preparations to deploy Russia’s new Sarmat intercontinental ballistic missile are well underway.

10.19.23 | 4 min read
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Nuclear Weapons
Blog
Strategic Posture Commission Report Calls for Broad Nuclear Buildup

In contrast to the Biden administration’s Nuclear Posture Review, the Congressionally-mandated Strategic Posture Commission report is a full-throated embrace of a U.S. nuclear build-up.

10.12.23 | 12 min read
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Nuclear Weapons
Report
Nuclear Notebook: Pakistan Nuclear Weapons, 2023

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans […]

09.14.23 | 1 min read
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Nuclear Weapons
Blog
Increasing Evidence that the US Air Force’s Nuclear Mission May Be Returning to UK Soil

New U.S. Air Force budgetary documents strongly imply that the United States Air Force is in the process of re-establishing its nuclear weapons mission on UK soil.

08.28.23 | 4 min read
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Nuclear Weapons
Blog
While Advocating Nuclear Transparency Abroad, Biden Administration Limits It At Home

Earlier this spring, the Department of Defense and Department of Energy twice rejected requests from the Federation of American Scientists to declassify the number of nuclear weapons in the US stockpile and the number of nuclear weapons awaiting dismantlement.

07.31.23 | 5 min read
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Nuclear Weapons
Blog
Belarus’ “Nuclear-Capable” Iskanders Get A New Garage

The Belarusian military has completed what appears to be a new garage facility for the allegedly nuclear-capable Iskander missile launchers it received from Russia.

07.27.23 | 2 min read
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Nuclear Weapons
Report
Nuclear Notebook: French Nuclear Weapons, 2023

The FAS Nuclear Notebook is one of the most widely sourced reference materials worldwide for reliable information about the status of nuclear weapons and has been published in the Bulletin of the Atomic Scientists since 1987. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: Director Hans […]

07.19.23 | 1 min read
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Nuclear Weapons
Blog
Does Russia Have Nuclear Landmines?

Recent U.S. Intelligence reports refer repeatedly to the existence of Russian nuclear landmines, although it is uncertain how operational they are.

07.17.23 | 6 min read
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