How to read the band →
Solid line = floor (spellings that unambiguously belong to the group). Shaded band up to the dashed edge = ceiling (the most it could reach if every ambiguous spelling counted here).
Isabella
Isabella has been easing down from its peak but is still widely used. All-time it's been given to 463,803 U.S. babies, the 13th most common name by sound today, peaking at 25,937 in 2010, with 11,652 in 2025.
By sound, Isabella also includes the spellings Izabella, Isabela, Izzabella.
Rising