Ibn 'Abbas (May Allah be pleased with them) reported:
The Prophet (ﷺ) said, "(The performance of) 'Umrah during Ramadan is equal to Hajj (pilgrimage)." Or said, "Equal to the performance of Hajj with me."[Al-Bukhari and Muslim]. (IT)
App reference (IT): Book 11, Hadith 8 (IT)
Arabic/English book reference (IT): Book 11, Hadith 1278 (IT)