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Caidyn vs Cairo

American parents have registered 9,999 Cairos since 1880, against 1,270 Caidyns. Cairo is still ahead, with 1,000 babies in 2025.

Babies given each name, 1880–2025

Births per year: Caidyn against Cairo, 1880 to 2025 0 300 600 900 1.2k 1880 1900 1920 1940 1960 1980 2000 2020

Caidyn Cairo

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

Of the 40 years in which either name was published, Cairo for 32 years and Caidyn for 8 years. The lead changed hands 2 times.

Side by side

  Caidyn Cairo
Total US births 1,2709,999
Most in one year 951,157
Babies in 2025 231,000
Estimated living today 1,3009,900
Median age today 144
Peak year 20112022
Best rank 2,077th boys306th boys
Rank in 2025 4,396th341st
First recorded 19991979
Girls / boys 440 / 830584 / 9,415

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 Caidyns alive today are over 14; half the Cairos are over 4. That is 10 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 Caidyn Cairo
Scotland 337

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: Caidyn and Cairo.