By net wealth (assets - liabilities). Here's a Wikipedia list (https://en.wikipedia.org/wiki/List_of_countries_by_total_wea...) based on the Credit Suisse Global Wealth Report (https://www.credit-suisse.com/about-us/en/reports-research/g...). You're right that it's not even close, the US is almost twice as rich as China in the #2 spot.