| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Kaisa | KIE-sah (Finnish) | Finnish, Estonian | ||
| Kaja (1) | KAH-yah (Swedish, Estonian) | Norwegian, Danish, Swedish, Estonian, Slovene | ||
| Kaja (3) | KAH-yah | Estonian | ||
| Kalev (1) | - | Estonian | ||
| Kalju | - | Estonian | ||
| Katariina | KAH-tah-ree:-nah (Finnish) | Finnish, Estonian | ||
| Kati | KAH-tee (Finnish) | Finnish, Estonian, Hungarian | ||
| Katrin | kah-TREEN (German, Swedish) | German, Swedish, Estonian | ||
| Koit | - | Estonian | ||
| Kristiina | KREES-tee:-nah (Finnish) | Finnish, Estonian | ||
| Kristjan | - | Estonian, Slovene | ||
| Lagle | - | Estonian | ||
| Laine | LIE-ne | Estonian | ||
| Laura | LAWR-ə (English), LOW-rah (Spanish, Italian, Finnish, Polish, Swedish, Norwegian, Danish, German, Dutch), LAW-oo-raw (Hungarian) | English, Spanish, Italian, Portuguese, Romanian, Finnish, Estonian, Hungarian, Polish, Slovene, Croa | ||
| Leelo | - | Estonian |