| SgM | SgF | SgN | PlM | PlF | PlN | |
| Nom | breiðr | breið (rule) | breitt (rule) | breiðir (rule) | breiðar (rule) | breið (rule) |
| Acc | breiðan (rule) | breiða (rule) | breitt (rule) | breiða (rule) | breiðar (rule) | breið (rule) |
| Dat | breiðum (rule) | breiðri (rule) | breiðu (rule) | breiðum (rule) | breiðum (rule) | breiðum (rule) |
| Gen | breiðs (rule) | breiðrar (rule) | breiðs (rule) | breiðra (rule) | breiðra (rule) | breiðra (rule) |
| SgM | SgF | SgN | Pl | |
| Nom | breiði (rule) | breiða (rule) | breiða (rule) | breiðu (rule) |
| Acc | breiða (rule) | breiðu (rule) | breiða (rule) | breiðu (rule) |
| Dat | breiða (rule) | breiðu (rule) | breiða (rule) | breiðum (rule) |
| Gen | breiða (rule) | breiðu (rule) | breiða (rule) | breiðu (rule) |
| Degree | |
| Comp | breiðari (rule) |
| Sup | breiðastr (rule) |