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Kaci vs Kacper

American parents have registered 10,183 Kacis since 1880, against 1,102 Kacpers. Kaci is still ahead, with 99 babies in 2025.

Babies given each name, 1880–2025

Births per year: Kaci against Kacper, 1880 to 2025 0 100 200 300 400 1880 1900 1920 1940 1960 1980 2000 2020

Kaci Kacper

Each line is every baby given the name that year, girls and boys added together — the only count that means the same thing for both names. A line breaks where the name fell below five babies in a year — the point at which the SSA stops publishing it — rather than being drawn through a figure nobody published. A single published year in a gap shows as a dot.

Who was ahead

Kaci has been the commoner name in every year either was published, 1965 to 2025. The lead has never changed hands.

The closest they came was 2012, when Kaci had 129 and Kacper had 62.

Side by side

  Kaci Kacper
Total US births 10,1831,102
Most in one year 36288
Babies in 2025 9911
Estimated living today 10,0001,100
Median age today 2817
Peak year 19902007
Best rank 620th girls1,713th boys
Rank in 2025 2,117th7,194th
First recorded 19651994
Girls / boys 10,009 / 1740 / 1,102

A rank is a position within one sex’s list for one year, so the two rank rows are not subtracted from one another and the winning column is not marked on them. The living figure is a life-table estimate, not a count.

Which name is older

Half of the Kacis alive today are over 28; half the Kacpers are over 17. That is 11 years between them: two names in use at the same time, worn by two different generations.

Where each one is strongest

How much commoner the name is in that state than it is nationally, from births recorded since 1910.

Both names abroad

Countries whose statistics office publishes both names, so the comparison can be made somewhere other than the United States.

Country Kaci Kacper
England and Wales 1,8994,408
Ireland 234848
Scotland 266428
France 365165
Northern Ireland 146161

Every spelling a country files separately is added together, over whatever years that country publishes — which is not the same range in any two of them, so read the columns against each other and not the rows.

Compare something else

Related comparisons

Social Security Administration birth records, 1880–2025, public domain. Full histories: Kaci and Kacper.