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Theodor vs Theresa

American parents have registered 405,831 Theresas since 1880, against 2,216 Theodors. Theresa is still ahead, with 136 babies in 2025.

Babies given each name, 1880–2025

Births per year: Theodor against Theresa, 1880 to 2025 0 3k 6k 9k 12k 1880 1900 1920 1940 1960 1980 2000 2020

Theodor Theresa

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

Theresa has been the commoner name in every year either was published, 1880 to 2025. The lead has never changed hands.

The closest they came was 2023, when Theodor had 86 and Theresa had 123.

Side by side

  Theodor Theresa
Total US births 2,216405,831
Most in one year 8811,991
Babies in 2025 76136
Estimated living today 1,700266,000
Median age today 1262
Peak year 20221961
Best rank 1,826th boys35th girls
Rank in 2025 1,992nd1,548th
First recorded 18841880
Girls / boys 0 / 2,216404,613 / 1,218

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 Theresas alive today are over 62; half the Theodors are over 12. That is 50 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 Theodor Theresa
Austria 2,84210,779
Norway 5,414238
France 3652,285
Ireland 471,965
England and Wales 800664
Switzerland 548119
Scotland 14504
Belgium 12420
Poland 1242
Northern Ireland 68

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: Theodor and Theresa.