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Tadashi vs Tadeo

American parents have registered 5,843 Tadeos since 1880, against 676 Tadashis. Tadeo is still ahead, with 753 babies in 2025.

Babies given each name, 1880–2025

Births per year: Tadashi against Tadeo, 1880 to 2025 0 200 400 600 800 1880 1900 1920 1940 1960 1980 2000 2020

Tadashi Tadeo

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 69 years in which either name was published, Tadeo for 36 years and Tadashi for 33 years. The lead changed hands 7 times.

Side by side

  Tadashi Tadeo
Total US births 6765,843
Most in one year 35782
Babies in 2025 11753
Estimated living today 1905,800
Median age today 84
Peak year 19222024
Best rank 1,222nd boys412th boys
Rank in 2025 7,194th427th
First recorded 19121968
Girls / boys 0 / 6760 / 5,843

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 Tadashis alive today are over 8; half the Tadeos are over 4. That is 4 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.

Compare something else

Related comparisons

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