夜更かしなど平気だ。

夜更かしなど平気だ。

Staying up late nights is nothing to me.

夜(よる)更(ふ)かしなど平気(へいき)だ。

Yoru fukashi nado heiki da.

夜 (よる、よ)

evening; night

更かす (ふかす)

to sit up late

等 (など)

et cetera; etc.; and the like; and so forth; or something; the likes of

平気 (へいき)

coolness; calmness; composure; unconcern; all right; OK; okay

だ (だ)

be; is; indicates past or completed action; indicates light imperative

Readings: ヤ、よ、よる

Meanings: night, evening

Readings: コウ、さら、さら.に、ふ.ける、ふ.かす

Meanings: grow late, night watch, sit up late, of course, renew, renovate, again, more and more, further

Readings: ヘイ、ビョウ、ヒョウ、たい.ら、 -だいら、ひら、ひら-

Meanings: even, flat, peace

Readings: キ、ケ、いき

Meanings: spirit, mind, air, atmosphere, mood