How do you say "I'm tired/sleepy"
眠たいです?

Does it sound childish if you use this word, and is this the best way to say it?

Question

How do you say "I'm tired/sleepy"
眠たいです?

Does it sound childish if you use this word, and is this the best way to say it?

Answer

眠たいです is a correct way to express that you're tired!

You can also just say

眠いです = I am tired

You can also express being tired by saying "疲れる" (つかれる)

For example:

昨日私は疲れました。
I was tired yesterday.

Updated! Thanks for the correction.

Answer

「眠いの」

Answer

You can also use 寝たい(ねたい)