The Prophet ﷺ used to pray nine rakats during the night.
حدثنا هناد بن السري حدثنا أبو الأحوص عن الأعمش عن إبراهيم عن الأسود
أن النبي ﷺ كان يصلي من الليل تسع ركعات
[Sahih] Reported by Tirmidhi, Prayer, a chapter on it, no. 443, from Hannad, and he said, "Sahih." It has supporting narrations in Muslim, Prayer of the Traveler, chapter on the permissibility of the voluntary prayer standing or sitting, etc., no. 730, and elsewhere.