The musician and producer, who won a Golden Globe for his score to the 2014 Stephen Hawking biopic starring Eddie Redmayne, was found dead in Berlin on Friday.
His representatives, Redbird Music Management, announced the news on Facebook, writing: "It is with profound sadness that we confirm the passing of our dear friend Johann."
"We have lost one of the most talented and brilliant people who we had the privilege of knowing and working with.
"May his music continue to inspire us."
Known for blending electronic with classical orchestrations, Johannsson was nominated for an Oscar and Bafta for his soundtrack to Denis Villeneuve's 2015 film, Sicario, and collaborated again with the director on 2016's sci-fi film Arrival.
He is survived by his parents, sisters and daughter.
Among those paying tribute following the news were experimental producer Flying Lotus and film director Aaron Moorhead.
Broadcaster Edith Bowman wrote on Twitter: "This is just the saddest of news. RIP Johann, your vision and creations will eternally inspire and influence me. Love and thoughts to all family and friends."
Flying Lotus posted: "Johann Johansson has been such an influence, especially lately. I'm in disbelief. The stuff he did for panoscosmatos "Mandy" is incredible."
Moorhead tweeted: "We just lost Johann Johannsson, one of the best composers in the world. Died just as he was getting started. Throw on IBM 1401 all day, The Sun's Gone Dim is like he wrote his own requiem. This is devastating."
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