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).
Tessa
Tessa is now well below its former popularity. All-time it's been given to 55,939 U.S. babies, the 671st most common name by sound today, peaking at 1,753 in 2007, with 978 in 2025.
Tessa has no common alternate spellings by sound.
Rising
Source: U.S. Social Security Administration, “National data” baby-names files (1880–2025).