Explanation

  • An informal way of saying I cannot do that, It's not possible, or I am unable to comply.

Origin

  • Often attributed to Chinese Pidgin English from the 19th century, mimicking sentence structures where ability/modality might precede the verb (can do, no can do).
  • It entered general English as a colloquial, sometimes slightly humorous or folksy, expression of inability.

Alternatives

Slang/Informal:

  • That's a no-go.
  • Ain't happening. / Not gonna happen.
  • Forget it. / Forget about it.
  • Nope, can't swing it.

Vulgar/Emphatic (Strong refusal/impossibility):

  • No fucking way.
  • Not a chance in hell.
  • Absolutely fucking not.

Milder/Standard:

  • Sorry, I can't do that.
  • Unfortunately, that's not possible.
  • I'm unable to assist with that. (Formal)

Situational Appropriateness

  • Informal.
  • Best suited for casual conversations with friends, family, or sometimes familiar colleagues.
  • Avoid in formal settings; it can sound unprofessional, overly casual, or even slightly uneducated depending on the context and listener. I'm unable to or That's not possible are better formal choices.

Misunderstanding Warnings

  • The non-standard grammar (No can do vs. I cannot do) might initially confuse learners.
  • However, the meaning cannot is usually easily inferred from context.

Examples

  • Can you fix my computer by lunchtime? Sorry, too many repairs ahead of you. No can do.
  • Hey, can I borrow your car this weekend? Wish I could help, pal, but no can do. I need it.
  • Can we get this report done a day early? With the current workload? No can do.

Dialogue

Kid: Dad, can you build me a treehouse this afternoon?

Dad: (Looking at a long list of chores) Haha, I wish! No can do today, sport. Maybe we can plan it for next month?

Kid: Aww, okay.

Social Media Examples

  • Replying to a request in a hobby group: Can someone 3D print this obscure part for me? -> Checked my filament stock, sorry, no can do on that color right now.
  • Casual chat: Can you grab pizza on your way home? -> Ah! Traffic is insane. No can do, gonna be late as it is.

Response Patterns

  • The requester usually accepts the informal refusal.
  • Ah, okay. / Gotcha. / Alright, thanks anyway.
  • That's a shame.
  • They might ask for a reason if one isn't given.

Common Follow-up Questions/Actions

After the refusal:

  • The requester might ask Why not? or seek another way to achieve their goal.
  • The refuser might optionally offer a brief explanation.

Action:

  • The request is understood as unfulfillable by this person/in this way.

Conversation Starter

  • No.
  • It's a response indicating inability or impossibility.

Intonation

  • Casual, often definitive.
  • Can sound apologetic (Sorry, NO can DO.) or firm/final.
  • Stress often on No and do.

Generation Differences

  • Understood by most generations.
  • Might feel slightly dated or be used more frequently by older generations, but still persists in general informal use.

Regional Variations

  • Widely understood across major English-speaking regions, though perhaps felt to be characteristically American English by some.
Thanks, but no thanks