Dunno means I don't know, as the phrase sounds in fast speech. In texts to friends, people write it the way it sounds: I dunno or just Dunno. The tone is casual. It's fine with friends and family, but with a customer, teacher, colleague or IELTS examiner, it's better to say I'm not sure or I don't know.
Could you drop dunno into a text?
Write a short message — we'll show the mistakes right away and suggest how to say it more naturally.
The check is taking longer than usual. Your feedback will appear here automatically.
(I) dunno + what/where/if…; dunno, maybe…; Where's Tom? — Dunno.
- I dunno where I left my keys, can you check the car?
- Dunno if the shop's still open, it's nearly nine.
- I dunno, maybe we should just order pizza tonight.
What changed
First versionSorry, sir, I dunno when the manager will be back.
RevisionSorry, sir, I'm not sure when the manager will be back.
A shop assistant is speaking to a customer, and dunno sounds careless, as if brushing them off. With strangers and customers you need a neutral phrase: I'm not sure is more polite and softer than even the full I don't know.
Dunno and idk mean the same thing, but idk is an abbreviation made of first letters, and it lives in texting. Dunno reflects how I don't know sounds out loud, so people both say and write it: Who's coming tonight? — Dunno, ask Kate.
Your turn
My flatmate asked where the charger was. I texted back: ___, maybe Sam took it.
Show the answer
dunno — Your flatmate asks where the charger is, and you don't know but offer a guess about Sam: that's dunno. Nope is a casual no, an answer to a yes-or-no question, and it can't answer a where question.
A classmate asks in the group chat what time tomorrow's class starts. Reply with dunno and suggest who they could ask.
Dunno, ask Anna, she always knows the timetable.
Learn to use new words without mistakes
Write phrases with the words you are learning. LetsWords shows mistakes in usage and grammar, suggests corrections and explains them, and review helps the words stick.