Colonel Viktor Kalnitski was born in Tallinn on February 1, 1975.
He started his conscript service in the Estonian Defence Forces in 1994. After the conscript service, he attended the Infantry Senior NCO Course at the Estonian Defence Forces’ Battle School. After graduating from the course, he continued his service as Platoon Sergeant, and later as Platoon Leader in Single Infantry Company North.

From 1996 to 1998, he served as Platoon Leader of the Reconnaissance Platoon of the Single Guard Battalion. In 1998, he was selected to take an Infantry Officers’ Course at the Finnish Reserve Officers' School. Upon completion of the reserve officers’ course, he continued his studies at the Finnish National Defence University. During university studies, there was an opportunity to expand the knowledge and change the branch, and as a result he chose field artillery as his new specialization.

In 2002, he graduated from the university with a Master's Degree and returned to Estonia, where he continued his service in the Artillery Battalion. There he served as Battery 2IC, Battery Commander, COS and finally Battalion Commander. In 2007, he was assigned to the G35 department of the Land Forces Command, initially as Staff Officer and later as Artillery Inspector. In 2008-2009, he studied at the Finnish National Defence University at the Senior Staff Officer’s Course.

He served as a SO J5/POLICY of the Headquarters Multinational Corps Northeast from 2013 to 2016. In 2016, he was rotated to the Estonian Defence League, where he served for a year in the Headquarters as G3/Branch Chief Operations, and two years as Viru district Commander and Commander of the Territorial Defence Region Northeast in Eastern Estonia.

In 2019, he continued his studies at the Finnish National Defence University's General Staff Officer’s Course. Upon graduation, he served at the Headquarters of the Estonian Defence Forces, initially as ACOS J1, and later as ACOS J7.

Colonel Kalnitski has participated three times in missions in Afghanistan – both in ISAF and in Resolute Support. He served in Helmand Province in 2008 as National Contingent Fire Support Officer and 2010-2011 as National Contingent Commander. From July 2014 to January 2015, he served as Staff Officer in IJC CJ55 and ISAF/RS HQ Afghan Assessment Group.

During his service, Colonel Viktor Kalnitski has completed various advanced studies and courses both in Estonia and abroad. He speaks Estonian, English, Russian and Finnish, and can also survive in Polish and Ukrainian language environments. Col Kalnitski has been awarded medals and decorations of the Estonian Defence Forces, NATO and the U.S.A.

He is married to Jelena, and they have a grown-up son, Aleksandr.