Girl Names That Start With O

Girl names that start with O in the 2025 data

O is the nineteenth most common first letter for girls born in 2025: 27,135 of them, 1.7% of every girl in the file. It has climbed from twentieth place a decade ago, and its share has grown from 1.4% to 1.7%.

This list holds the 22 of those names that reached the top 500 as a girl's name at some point since 1880 and are still given to girls rather than boys. The most common today is Olivia, #1 with 13,544 girls in 2025. 1 of the 22 are in this year's top 100, and 17 appear in the 2025 file at all — which takes at least five births, the point below which a name is left out. Two other names starting with O are left out — Odell and Odie. Each reached the top 500 among girls at some point, but fewer than one in ten children given it over the last ten years was a girl. Together they account for 23,438 of those 27,135 girls — the remainder go to names that have never reached the top 500, each given to a handful of children.

The fastest climber among them is Oaklynn, up from #3,001 in 2015 to #153 in 2025. The shortest name here is Oda at 3 letters, the longest Ottilie at 7.