Klaas-Jan de Groot (b. 1993) started his musical path at a young age, as a boy soprano in the Kampen Boys Choir. After his studies at the Royal Conservatoire in The Hague (NL) and the Royal Welsh College of Music & Drama (UK) he started to work as a professional conductor and chorus master.
From 2016 until 2022 Klaas-Jan was assistant chorus master at Dutch National Opera, assisting Ching-Lien Wu. He has assisted on numerous productions, amongst others the big operas by Verdi, Puccini and Wagner. With the chorus of DNO he has also been chorus master for various opera productions and other choral projects. In the season 2022-2023 Klaas-Jan was chorus master at Dutch National Opera for the world premiere of Eurydice by Manfred Trojahn, a revival of Don Giovanni and new productions of Anna Bolena and Tosca.
As guest chorus master, Klaas-Jan has prepared the Netherlands Radio Chorus (Groot Omroepkoor) for performances of Nabucco, Semiramide, Il piccolo Marat, Jenufa, Fedora, Kullervo, Norma and Beethoven 9 in the Concertgebouw in Amsterdam. He also prepared the chorus for a recording of Schaduwen over Atlantis by Karel Mengelberg.
In the summers of 2018, 2019, 2021, 2022 and 2023 Klaas-Jan worked as assistant chorus master at the Bayreuther Festspiele on all Wagner operas.
With the Orchestra of the 18th century Klaas-Jan was assistant conductor for semi-staged performances of Don Giovanni (2019) and Der Schauspieldirektor (2021). Of the latter he also conducted one performance in the concert hall in Zwolle.
At Opera Zuid (Maastricht) Klaas-Jan has worked on many productions as chorus master and assistant conductor. Here he also conducted several performances (Un ballo in maschera and Fantasio) with the orchestra of Philharmonie Zuid-Nederland.
In 2020-2021 Klaas-Jan prepared the Rotterdam Symphony Chorus for two livestreams of Beethoven IX and Bach's Matthäus Passion.
In 2021 Klaas-Jan was awarded the prestigious conducting prize from the Anton Kersjesfonds, as a bursary to further support his development and career.
In 2022 Klaas-Jan joined the Aalto-Theater in Essen as their principal chorus director. In May 2023 he started to work with the NDR Vokalensemble in Hamburg.
As of season 2025-2026 Klaas-Jan de Groot will be principal chorus master of Opernhaus Zürich.