According to this, you can calculate HRA by Filing in the basic details on a per annum basis:
   Benefits 
You can use this online HRA calculator as many times as you want without making a single mistake.
HRA calculator allows you to claim tax exemptions on the basis of the calculations.
This calculator takes care of all the variables that are a part of HRA calculation quickly and efficiently.
  
                    FAQs 
FREQUENTLY ASKED QUESTIONS