Kristina Pfeffer has studied piano in Tallinn Nõmme Music School and music theory in Georg Ots Music College, where she began playing organ (in class of Kristel Aer). In 2012 she graduated Tallinn College of Tallinn University of Technology major in business law. In 2010-2016 she had been studying organ at Estonian Academy of Music and Theatre supervised by prof. Andres Uibo. 2012-2013 she  studied in prof. Hartmut Rohmeyer organ class in Lübeck, Germany. She also took lessons with Echo-Klassik-Preis winner organist Christian Schmitt in Stuttgart.

Kristina Pfeffer has taken part in several master classes including with Guy Bovet, Michael Radulescu, Edouard Oganessian, Peter van Dijk, Martin Sander, Alexey Schmitov etc. In 2013 she started to compose music and won a prize on a composition competition, organized by Estonian Union of Sacred Music.
Kristina Pfeffer worked as a music theory and solfeggio teacher in Lasnamäe Music School in Tallinn and as a church organist in Lutheran church in Keila. She also worked as concert organist in the St. Nicholas Museum-Concert Hall.
Kristina Pfeffer plays regularly concerts in Estonia, Germany, Belgium, Switzerland, Latvia etc. She gave a concerts in frame of big festivals like Tallinn International Organ Festival, BachFest Tallinn, SICG Stuttgart and Antwerp International Organ Festival. She is the member of Association of Estonian Professional Musicians.

Kristina Pfeffer worked as an organist in Gedächtniskirche Stuttgart.

She also worked as a choir assistant in "Figuralchor" in Stuttgart (conductor Alexander Burda). 

In 2018-2024 she was studying bachelor and master of church music in the University of Church Music Tübingen, Germany. Her teachers are Prof. Jens Wollenschläger (Organ), Prof. Thomas J. Mandl (Conducting), Prof. Patrick Bebelaar (Jazz Piano) etc. From October  2024 she studies in Dresden Music University Master of Choir Conducting.

She was conducting a pop choir "Cocktail Vocale" in Sindelfingen and since September 2021 a choir in Sickenhausen/Degerschlacht (Reutlingen). Beginning from October 2024 she is working as an church musician assistant of Jörg-Hannes Hahn in Bad Cannstatt (Stuttgart)

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