Alga is a very rare girls' name that was most common in the 1910s and has all but disappeared.
Alga is predominantly a girl name. It last appears in U.S. records in 1955. Alga first appears in 1888 and peaked in 1915 (11 births).
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 1955 | 5 | — | #5,840 | — |
| 1931 | 5 | — | #4,347 | — |
| 1930 | 11 | — | #4,056 | #4,011 |
| 1928 | 6 | — | #4,205 | — |
| 1927 | 5 | — | #4,818 | — |
| 1926 | 6 | — | #4,318 | — |
| 1925 | 6 | — | #4,437 | — |
| 1923 | 5 | — | #4,982 | — |
| 1922 | 7 | — | #4,022 | — |
| 1921 | 8 | — | #3,676 | — |
| 1920 | 9 | — | #3,344 | — |
| 1919 | 6 | — | #4,265 | — |
| 1918 | 11 | — | #2,827 | — |
| 1917 | 8 | — | #3,353 | — |
| 1916 | 9 | — | #3,041 | — |
| 1915 | 11 | — | #2,535 | — |
| 1914 | 6 | — | #3,195 | — |
| 1903 | 8 | — | #1,320 | — |
| 1888 | 5 | — | #1,284 | — |