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).
Grace is down from its peak but still widely used. All-time it's been given to 540,764 U.S. babies, the 130th most common name by sound today, peaking at 12,915 in 2003, with 5,154 in 2025.
By sound, Grace also includes the spellings Grayce.
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).