The companion of the Messenger of Allah, Sayyiduna Safinah (may Allah be pleased with him), narrates that the Messenger of Allah (peace and blessings be upon him) used to perform ghusl with one sa’ of water and used to perform wudu with one mudd of water.
Hadith Referenceالمنتقى ابن الجارود / كتاب الطهارة / 62
Hadith Gradingغلام مصطفےٰ ظهير امن پوري: صحيح مسلم