وَأَقَلُّ الْحَيْضِ ثَلَاثَةُ أَيَّامٍ وَلَيَالِيهَا، وَأَوْسَطُهُ خَمْسَةٌ، وَأَكْثَرُهُ عَشَرَةٌ
• Minimum possible Hayd: 3 days and nights.
• Average stated by the text: 5 days.
• Maximum possible Hayd: 10 days.
Bleeding shorter than the minimum is Istihadah. Bleeding continuing beyond the maximum involves Istihadah; for a woman with an established habit, detailed allocation must take that habit into account rather than automatically calling the first 10 days Hayd in every case.