KALVIS KALNIŅŠ began his vocal studies in 2009 at Jāzeps Mediņš Riga Music Secondary School in the class of Krišjānis Norvelis, graduating with honours in 2013. During this period, he received accolades in various local and international competitions. He continued his studies at the Jāzeps Vītols Latvian Academy of Music, where he earned his bachelor’s degree in Krišjānis Norvelis’ class and his master’s degree in Andžella Goba’s class. Kalniņš also studied at the Vienna Academy of Music and Performing Arts under Professor P. Edelmann. He made his debut as a soloist with the Latvian National Opera in G. F. Handel's oratorio Messiah, performing in the soloist ensemble. He also had a successful debut in Finland, performing as Count Almaviva in W. A. Mozart's Le nozze di Figaro in a production by the Helsinki Sibelius Academy Opera Studio. Kalvis Kalniņš has developed a strong collaboration with vocal coach Margarita Gruzdeva, with whom he currently continues his vocal training.

Kalvis Kalniņš' repertoire at the Latvian National Opera includes such roles as Valentin and Wagner in Charles Gounod's Faust, Peter Skudritz in Zigmārs Liepiņš's The Rose of Turaida, Biterolf in Richard Wagner's Tannhäuser, Dancaïre in Georges Bizet's Carmen, Orlofsky in Strauss's Die Fledermaus, Papageno in Die Zauberflöte, The Birds Seller in Jānis Lūsēns' The Birds’ Opera, Figaro in Gioacchino Rossini's Il Barbiere di Siviglia, Malatesta in Gaetano Donizetti's Don Pasquale, Ping in Giacomo Puccini's Turandot, Dandini in Gioacchino Rossini's Cinderella, Horatio and Prologue in Jānis Kalniņš' Hamlet, Cascade in Franz Lehár's Die lustige Witwe, etc.