Allah's Messenger (ﷺ) enjoined the payment of one Sa' of dates or one Sa' of barley as Zakat-ul-Fitr on every Muslim slave or free, male or female, young or old, and he ordered that it be paid before the people went out to offer the `Id prayer. (One Sa' = 3 Kilograms approx.)
Sahih al-Bukhari Book 24, Hadith 103
← Previous Hadith I took `Abdullah bin Abu Talha to Allah's Messenger (ﷺ) to perform Tahnik for him. (Tahnik was a custom among the Muslims that whenever a child was born they used to take it to the Prophet (ﷺ) who would chew a piece of date and put a part of its juice in the child's mouth). I saw the Prophet (ﷺ) and he had an instrument for branding in his hands and was branding the camels of Zakat.

Sahih al-Bukhari Book 24, Hadith 102 Next Hadith → Allah's Messenger (ﷺ) made it incumbent on all the slave or free Muslims, male or female, to pay one Sa' of dates or barley as Zakat-ul-Fitr.

Sahih al-Bukhari Book 24, Hadith 104