India is an absolutely enormous and incredibly diverse place, so did you have a particular region in mind?

Angus Maddison is the economic historian known best for attempting to conduct these kinds of comparisons consistently across time and space: his own view is that living conditions were lower around 1850 than they were in 1500 (see e.g. here, though he has written about South Asia at greater length elsewhere. If you wanted to take his figures literally, he estimates GDP per capita (in 1990 $, PPP) at 550 in 1500 and 533 in 1850.

Scholars take his figures with plenty of salt, but, in terms of sign and magnitude, I don't think that's far from the consensus view of most mainstream economic historians - no improvement at best, and most likely mild decline. But as /u/gh333 says, it matters a lot where you mean (urban centers would certainly have been richer, as well as trading ports; Bengal was more developed in the 18th century than many other parts of the subcontinent).

Very little of that comparison has to do with British rule directly - the disintegration of the Mughal Empire was pretty terrible for growth, and there weren't great signs of improvement in agricultural productivity (of the kind which preceded the Industrial Revolution in Britain). The slow growth of population is quite telling, I think: roughly speaking, population doubled over that period (which is very slow - consider that India's population doubled again in the following century).