عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ كَانَ يُكَبِّرُ فِي الْعِيدَيْنِ سَبْعًا فِي الرَّكْعَةِ الْأُولَى، وَخَمْسًا فِي الْآخِرَةِ سِوَى تَكْبِيرَتَيِ الرُّكُوعِ
Sayyidah Aisha (may Allah be pleased with her) says that indeed the Messenger of Allah (peace and blessings be upon him) used to say seven takbirs in the first rak'ah and five takbirs in the second rak'ah in the Eid prayers; these were in addition to the takbirs of bowing (ruku).