Quick answer
no pasa nada
Natural: no worries / it’s fine / never mind
Literal: “nothing happens”
How it is used
— Perdón, llego tarde. — No pasa nada.— Sorry I’m late. — No worries.
Se me ha roto el vaso. — No pasa nada.I’ve broken the glass. — Never mind.
No pasa nada si no puedes venir.It’s fine if you can’t come.
Tranquilo, no pasa nada.Relax, it’s all fine.
Where it is said
Everywhere, but especially Spanish-from-Spain in frequency. Mexico: no hay problema, ni modo. Argentina: no hay drama.
A mini dialogue
— Oye, no puedo quedar mañana.— Hey, I can’t meet up tomorrow.
— No pasa nada, ¿el jueves?— No worries, Thursday?
Watch out
no pasa nada
Not for serious matters. If someone’s father is ill, no pasa nada sounds cold — you want lo siento mucho. And it answers an apology, not thanks: after gracias the reply is de nada.
Check yourself
Someone says “gracias”. You reply: