Impact Index is an alternative statistical system in cricket. It was conceived by Jaideep Varma in March 2009 and unveiled in July that same year at the ICC Centenary Conference at Oxford.
The system measures the contribution of each player in the context of the impact that he has on the match, compared to the standard cricket statistics of batting average and bowling averaged or strike rate. It compares each player's performance to the other 21 players in the match, and for career assessments, it assigns a value of each player's performance of between 0 and 5.
In 2010, the T20 version of Impact Index was used as an “Official Stats Partner” for the Radiant Twenty20 USA tournament in the United States. The system was used to give out all the individual awards in the tournament.
When applied over the history of One Day International (ODI) cricket in January 2011, it determined that Viv Richards was the greatest ODI player of all time.
Jaideep Varma and Soham Sarkhel ran it out of Mumbai till mid-2014.
In June 2014, Impact Index became a part of Wisden India. It is now run out of Bangalore from Wisden House, Lavelle Road by Jaideep Varma, Soham Sarkhel, Nikhil Narain and Karthik Swaminathan.