China has the world’s largest army. Russia wields the most tanks. America owns the fanciest satellites. But who has the most cyber-power? A new National Cyber Power Index by the Belfer Centre at Harvard University ranks 30 countries on their level of ambition and capability. Offensive cyber-power—the ability to do harm in or through computer networks—is one measure. But so too are the strength of a country’s defences, the sophistication of its cyber-security industry and its ability to spread and counter propaganda.

The Belfer National Cyber Power Index (NCPI) measures 30 countries cyber capabilities in the context of seven national objectives, using 32 intent indicators and 27 capability indicators with evidence collected from publicly available data.

Our intention is to provide the best possible understanding of cyber power capabilities to inform public debate. The Belfer approach proposes eight objectives that countries pursue using cyber means; provides a list of capabilities required to achieve those objectives that demonstrates the breadth of sources of cyber power; and compares countries based on their capability to achieve those objectives. Our work builds on existing cyber indices such as the Economist Intelligence Unit and Booz Allen Hamilton’s 2011 Cyber Power Ranking, by, for example, including a policy dimension and recognizing that cyber capabilities enhance military strength.