Over the past 110 years, 25 107 girls and 11 boys have been named Joni. The name Joni ranks 799th in the United States among the most common names for girls. For the first time more than ten times newborns were named Joni in 1939. The peak of popularity of the name Joni came in the 1950s and 1960s. You can see absolute numbers and relative numbers on the chart. Indicators per 100K more accurately assess the popularity of the name.