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).
Thomas
Thomas is down from its peak but still widely used. All-time it's been given to 2,367,087 U.S. babies, the 83rd most common name by sound today, peaking at 48,725 in 1952, with 6,924 in 2025.
Thomas has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).