Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) said, "Surat Ikhlas is equivalent to one-third of the Qur'an."[Muslim]. (ID)
App reference (ID): Book 9, Hadith 22 (ID)
Arabic/English book reference (ID): Book 9, Hadith 1012 (ID)