Compare two names
Killian and Cillian side by side: Killian peaked in 2017 and Cillian in 2024; in 2025 they were given to 785 and 595 babies.
Killian and Cillian, year by year
Girls and boys together; Killian solid, Cillian dashed.
| Killian | Cillian | |
|---|---|---|
| Births 2025 | 785 | 595 |
| Rank 2025 | #418 among boys’ names | #507 among boys’ names |
| Recorded since 1880 | 16,834 | 4,090 |
| Peak year | 2017 | 2024 |
| Girls | 4% | 0.1% |
| Alive, estimated | 16,600 | 4,060 |
| Median age | 9 | 4 |
Both names: SSA national file, published May 8, 2026, and SSA’s cohort life tables.