I've made this connection a lot of times. You have about three and three quarter hours, which is enough time IF the inbound flight is not delayed, and IF the international terminal is not exceptionally busy. International departures at T3 can get super crowded just past midnight (because that's when a lot of Europe/North America-bound international flights take off), so on an exceptionally busy day, you could be cutting it fine.
In my experience, security check and immigration check can take anywhere between 0.5 - 1.5+ hours at IGI T3. Unfortunately, there's nothing you can do to shorten this time. The baggage drop/check-in is the only part of the process you can somewhat control.
Therefore, I'd definitely perform a web check-in for the international flight beforehand so that I can proceed to the (usually much shorter) web check-in queue for baggage drop. If your airline offers priority check-in for a small fee, that might be a good option as well.
On your domestic flight, Jet, Vistara and some other airlines offer priority baggage claim for a fee as well, which means that when you collect your baggage from the domestic terminal, it should be among the first to arrive on the carousel, thereby saving you some valuable time.
Even without the priority check-in/baggage claim, you will most probably be fine, as long as you do the web check-in beforehand. On the outside chance that you are late, make sure you let the airline staff at T3 know that you might miss your flight; they will usually be able to help you by letting you cut across queues.