Violinist Kaido Välja was born in Tallinn in 1969. He has been working as a violin teacher at the Tallinn University of Music since 1992. In 2018, he was awarded an 8th degree teacher qualification.

In addition to his teaching work, he plays in the main Estonian orchestras and is actively involved in the activities of chamber ensembles. In 1993–2009, he worked in the Tallinn Chamber Orchestra, and since 1996, he has been concertmaster of second violins. Since 2010, he has been playing in the Estonian National Symphony Orchestra (concertmaster of second violins). He also plays as a soloist with this orchestra, performing programs of works by Baroque composers. He gives concerts in many European countries, as well as in Japan, Russia, and the USA. Kaido plays in various Baroque music ensembles and orchestras.

Since 2014, he has been the president of the Estonian String Instrument Teachers' Association.

Kaido Välja organizes summer camps for young string players in Värske, and in 2022 such a camp will be organized for the 25th time. He participated in the judging panel of the 5th International Saulius Sondeckis Competition for Young String Players and Pianists in 2017.

He also conducts mentoring lectures-masterclasses for Estonian string instrument teachers.

As a teacher, Kaidos conducts masterclasses not only in Estonia - in 2019 he participated in the 7th Birštonas Summer Academy, organized in Birštonas by the Lithuanian Musicians' Union, and has repeatedly participated in masterclasses at the Šiauliai Saulius Sondeckis Arts Gymnasium.

Riho Päts Music Foundation Annual Prize (2019).

Estonian Cultural Foundation Music Foundation Annual Prize (2021).