The world spends roughly 2.6% of its GDP on military purposes, according to SIPRI. While the United States is by far the largest spender in absolute terms (accounting for over 40% of global military spending), it is, together with Russia, also the largest spender in comparison to GDP (4.7% and 3.9% respectively in 2011).
While USA remains the only global superpower, its is China and India who are the largest in terms of armed personnel, with 2.95 mil and 2.63 mil soldiers at the end of 2010; however, one has to add that a quarter of Chinese and more than a half of Indian armed personnel are reserve personnel.
With more than 1.75 mil reserve personnel, the Indian Army is therefore the world's largest standing volunteer army
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