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).
Logan
Logan is down from its peak but still widely used. All-time it's been given to 419,837 U.S. babies, the 64th most common name by sound today, peaking at 16,039 in 2007, with 6,351 in 2025.
Logan has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).