Rudolf vs Rudolfo
American parents have registered 2,951 Rudolfs since 1880, against 2,263 Rudolfos. Neither name reached five babies in 2025.
Babies given each name, 1880–2025
Rudolf Rudolfo
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 127 years in which either name was published, Rudolf for 68 years and Rudolfo for 59 years. The lead changed hands 18 times.
8 shorter spells of a year or two are folded into the spans above rather than listed separately.
Side by side
| Rudolf | Rudolfo | |
|---|---|---|
| Total US births | 2,951 | 2,263 |
| Most in one year | 82 | 70 |
| Babies in 2025 | under 5 | under 5 |
| Estimated living today | 1,100 | 1,500 |
| Median age today | 58 | 54 |
| Peak year | 1927 | 1955 |
| Best rank | 716th boys | 885th boys |
| Rank in 2025 | unranked | unranked |
| First recorded | 1882 | 1914 |
| Girls / boys | 0 / 2,951 | 0 / 2,263 |
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 Rudolfs alive today are over 58; half the Rudolfos are over 54. That is 4 years between them: two names in use at the same time, worn by two different generations.
Where each one is strongest
- Rudolf New York (6.5×), Texas (1.9×), California (1.6×)
- Rudolfo Texas (7.8×), New Mexico (7.1×), California (3.3×)
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: Rudolf and Rudolfo.