Boy Names That Became Girl Names (and Vice Versa)
More names have shifted from boys to girls than the other way around. But in both directions, changes in girls’ naming trends drove most of the movement.
Picture a baby named Leslie, Kelly, or Ashley, and you’ll probably picture a girl. But all three names were once given mostly to boys. Looking at US baby names from 1936 to 2025, we found that 42 shifted from mostly boys to mostly girls, while just 12 went the other way. Explore the charts below to see how each name changed and what drove the shifts in each direction.
01 / Names
125 names that moved between boys and girls
The chart below follows 125 names whose use among boys and girls has changed noticeably over time. Of those, 54 meet our stricter definition of a switch from one sex to the other.
Each row is a name, and each tile represents a five-year period, running from 1936 on the left to 2025 on the right. The color shows what percentage of babies given each name were girls, while gray tiles mark periods with too few recorded births for a reliable comparison. Select any name to explore its history on the interactive see-saw chart below.
The names are grouped by how they’ve changed. Some, like Aubrey and Lindsey, shifted from mostly boys to mostly girls and stayed there, while others, like Jean and Ollie, moved in the opposite direction.
Not every name made a complete switch. Charlie and Blake were once given mostly to boys but have become unisex, with a much more even split today, while names like Jamie and Robin have changed direction along the way.
Moved toward girls (57)
Moved toward boys (16)
Became shared (17)
Changed direction (35)
02 / Direction
Most names moved toward girls, and girls drove the change both ways
The most common shift was from boys to girls. Using a consistent definition of what qualifies as a switch, we found that 42 names moved from mostly boys to mostly girls, compared with just 12 that moved from mostly girls to mostly boys.
But the more interesting finding is what drove these changes. Think of each name as a see-saw, with boys on one end and girls on the other. A name can tip toward girls in two ways: more girls start getting it, or fewer boys do.
For each name that switched, we compared how often it was given to boys and girls before and after the shift. Of the 42 names that moved toward girls, 34 were driven mainly by an increase among girls, rather than a decline among boys.
Surprisingly, the same pattern held in the opposite direction. Of the 12 names that moved toward boys, 9 shifted mainly because fewer girls were receiving them, rather than because more boys were. In other words, whichever way a name moved, the biggest change usually came from girls.
Choose a name below, then move through the years to watch its see-saw tip. For the 54 names that qualify as switches, the chart also shows which side drove the change.
Girls drove Kelly’s switch. At its peak, the name was 55 times as common among girls as it had been before. Boys used it more too, but by much less. Kelly switched in 1956–1960, when the name was more popular than ever. See Kelly’s full history
Looking at the names individually also reveals another difference: when these shifts happened in a name’s history. Of the 42 names that moved toward girls, 32 switched at a new high, when more babies were receiving the name than in any earlier five-year period. Kelly, Taylor, and Avery are all examples. Only 2 of the 12 names that moved toward boys did the same.
Several shifts toward boys, by contrast, came after a name had nearly disappeared. Jan, Jean, Joan, Jody, and Dominique had all fallen to less than 10% of their earlier peak by the time they switched. When Joan became mostly masculine in 2001–2005, just 1,435 babies received the name, down from 74,477 at its peak. These names didn’t shift toward boys because boys had started receiving them more often, but because their use among girls had fallen so sharply that the remaining boys made up the majority.
Taken together, these patterns show that names don’t move between boys and girls in quite the same way. Names that shift toward girls often do so as they reach new heights of popularity, while some of the clearest shifts toward boys happen long after a name has fallen out of favor. And whether a name becomes more feminine or more masculine, the biggest change usually comes from girls.
How we measured it
Source: US Social Security Administration national baby-name files, 1936–2025, grouped into consecutive five-year periods. We start in 1936 because SSA records for earlier birth years are less complete.
Girls’ share: For each name, we divided the number of girls given it by the total number of babies given it, based on sex recorded at birth. About 51% of US babies are boys, so an even split in naming rates corresponds to roughly 49% girls. We don’t adjust for this, since the difference is small compared with our 60% threshold.
The SSA omits names given to fewer than five babies of a particular sex in a year. For those years, we allow between 0 and 4 births and calculate the lowest and highest possible girls’ share. Tiles show the midpoint of that range and appear gray when a period has fewer than 100 recorded births or the possible range exceeds 10 percentage points.
What counts as a switch: A name must have been given to one sex at least 60% of the time for two consecutive five-year periods, each with at least 500 recorded births, and later meet the same threshold for the opposite sex across another two consecutive periods. The 60% threshold must hold across the entire possible range.
We applied these rules equally in both directions to all 5,536 names common enough to evaluate, counting each name at most once per direction. This excludes names that shifted before becoming common enough to measure, or too recently to confirm. Ashley, the most common name in the chart, is one example: although it was once predominantly masculine, it never reached 500 births in two consecutive periods while mostly given to boys.
What drove each switch: We measured how often boys and girls received each name per 100,000 babies of the same sex, so differences in the size of each generation wouldn’t distort the comparison. For each sex, we compared its highest usage rate from the switch onward with its highest rate before the switch. The main driver is the sex whose usage changed more.
The see-saw leans toward the sex with the larger share of the name in the period selected on the slider. It leans less in periods when the name was rare compared with its own peak. It opens on the period a name switched, or, for names that didn’t qualify as switches, on its biggest change.
When a name switched: We counted a switch as happening at a new high if the name had at least as many recorded births in its first switch period as in any earlier period. We counted it as happening after the name had faded if it had fewer than 10% as many births as at its earlier peak.
Which names appear in the chart: The chart includes every counted switch, along with other names that showed substantial changes in their use among boys and girls. These additional names had at least 1,000 recorded births in a qualifying five-year period and either changed by at least 30 percentage points in girls’ share between qualifying periods or met our definition of becoming shared.
Names are grouped as “became shared” if they were at least 80% one sex in their first qualifying period and 40–60% girls in the latest period. They are grouped as “changed direction” if their girls’ share moved at least 25 percentage points one way and later at least 25 points back.