The country confirmed the last million cases in just 20 days, faster than the US or Brazil which have higher numbers.
Testing has been expanded considerably in India in recent weeks but the situation varies across states.
Spurred by a low death rate, the nation continues to reopen even as new hotspots drive the surge in cases. But some states have imposed restrictions.
The recent measures include local, intermittent lockdowns, sometimes limiting activity in specific cities or districts.