Pentala Harikrishna became a grandmaster in 2001 at the age of 15 years 3 months and 5 days, the youngest Indian to gain the title until that time.
Won at most levels of India's age championships. Main achievements in the youth and junior divisions were winning the World U10 Championship 1996, Asian U14 Championship 1999, World Junior Champion 2004, Chess960 World Junior Championship 2006.
Asian Continental Champion 2011.
World Knockout Championships of 2001 (round 1) & 2004 (round 2).
World Cups of 2005 (round 3), 2007 (round 1), 2011 (round 2) & 2015 (round 2).
Main tournament wins were at the Commonwealth Championship 2001, category XV Sanjin Hotel Cup 2005, category 16 Essent Hoogoveen 2005, Marx Gyorgy Memorial 2006 & 2007, SPICE Cup 2008, Nancy International 2009, New York Open 2010, Tata B 2012, Cappelle la Grande 2012, Biel 2013, the Edmonton International 2015 and the PokerStars Isle of Man International 2015.
Represented India at every Olympiad from 2000 onward.
Also represented India at the:
- World Team Championships of 2010 (team bronze), 2011 & 2015
- Asian Teams Championships of 2003 (team silver), 2009 (team gold and individual bronze), and 2012 (team silver)
- Asian Games (Chess Division) of 2006 (team gold & individual silver) and 2010 (team bronze) and
- Asian Indoor Games (Chess) 2009 (team bronze).
Has also played in and won numerous medals in the European Club Cup and in the national leagues of Russia, China, Germany, Czech Republic, Hungary, Spain, Greece, United Kingdom, Spain, Bosnia & Herzegovina, and Turkey.