Isadore
#5,861 in the US in 2025
Isadore in the United States
Between 2016 and 2025 the name has been rising — up 28% as a share of boys' births.
SOURCE·US Social Security Administration, national baby-name data·Public domain. SSA lists a name only if it was given to at least 5 babies of that sex that year.·REVIEWED JUL 2026
Isadore in New Zealand
Isadore never reached 10 births in a single year in New Zealand, so it does not appear in the DIA file. That is a reporting floor, not a zero — the name may still have been registered here, just never ten times in one year.
SOURCE·NZ Department of Internal Affairs, births by first name·CC BY 4.0. DIA lists a name only if it was given to at least 10 babies of that sex that year.·REVIEWED JUL 2026
Decade by decade in the US
| Year | Rank | Births |
|---|---|---|
| 1880 | #640 | 9 |
| 1890 | #511 | 14 |
| 1900 | #469 | 24 |
| 1910 | #337 | 54 |
| 1920 | #426 | 198 |
| 1930 | #841 | 60 |
| 1940 | #1,156 | 33 |
| 1950 | #1,499 | 24 |
| 1960 | #1,910 | 18 |
| 1970 | #2,293 | 16 |
| 1980 | #3,615 | 11 |
| 1990 | #5,382 | 9 |
| 2000 | #7,416 | 8 |
| 2010 | #8,803 | 8 |
| 2020 | #4,855 | 19 |
Where in the United States
The states that registered Isadore most often since 1880. These are lifetime totals, so they track state population as much as local taste — a name common in Wyoming will never out-count California.
| State | Births |
|---|---|
| Pennsylvania | 674 |
| New York | 657 |
| Illinois | 258 |
| New Jersey | 187 |
| Massachusetts | 179 |
| Michigan | 142 |
| Ohio | 129 |
| Louisiana | 88 |
| Maryland | 74 |
| South Carolina | 53 |
How these figures are worked out
- Counts come straight from the registrars: the US Social Security Administration (1880–2025) and the New Zealand Department of Internal Affairs (1900–2025). Nothing is scraped from another names site.
- Ranks are computed against every name in that year's file, not just the ones this site publishes pages for — otherwise a rank would flatter every name we happen to list.
- The curve is drawn on births per 100,000 of that sex, not raw counts. Raw counts across eras are misleading: far more births were registered in 1957 than in 1890, so a flat count is a falling share.
- Each country hides small numbers — the US below 5 births a year, New Zealand below 10. A gap in a line is "below the floor", never "nobody".
SOURCE·US SSA (1880–2025) + NZ DIA (1900–2025) birth registrations·ranks and shares computed from the source files, see method·REVIEWED JUL 2026