Kai

“Hawaiian for 'sea'; also Persian for 'king' (multiple origins)” — Multiple origins (Hawaiian, Persian, Germanic)

Boy's name · #93 in the US (2025) · 2020s

Kai has appeared in US records since 1926 — best rank #59 (2022) · 70,232 babies named Kai all-time · 1 in 450 boys born in 2025.

Around the world: #23 in Australia (NSW) (2025) · #25 in Australia (QLD) (2025) · #32 in Australia (VIC) (2025) · #34 in Ireland (2025) · #39 in Netherlands (2025).

Appears in 2020-2025 birth records of 50 states. See the full state-by-state map on this page.

Famous Kais

Kai Siegbahn — Swedish physicist (1918–2007)
Kai Havertz — German association football player (born 1999)
Kai Hansen — German guitarist and singer
Kai Wegner — German politician
Kai Shibato — Japanese association football player

In stories & tradition

Kai Khosrow — Shahnameh
Kai Kobad — Shahnameh
Kai Darab — Shahnameh

What Kais become

Among 2,002 notable people named Kai:

Medical professionals appear 1.96× more often than among typical names — e.g. Kai Simons, Finnish physician (MD, PhD), biochemist and molecular biologist.

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