Let me know vs Tell me this

When to use each in English, with meaning, register, and examples.

Let me know

Top 1,000 (very common)

Tell me this

Top 2,000 (common)
Most common: Let me know
 Let me knowTell me this
Pronunciation🇬🇧 //lɛt miː nəʊ//🇺🇸 //lɛt mi ˈnoʊ//🇬🇧 //tɛl mi ðɪs//🇺🇸 //tɛl mi ðɪs//
MeaningTell me when you have information.Ask someone for information about something.
ExamplePlease let me know if you can come to the party.Can you tell me this, how does it work?
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
Collocationslet me know, let us know, let him knowtell me more, tell me why, tell me everything
Antonymskeep me in the dark, withhold information-
Common mistakesUsing 'let me knowed' instead of 'let me know'., Confusing with 'let me knew'., Overusing in formal contexts where more formal phrases are expected.Confused with 'tell me that' when referring to specific information., Using it in overly formal settings where a more polite request would fit better.
Usage notesCommonly used in casual and formal conversation. Best for requesting updates or information. Avoid in very formal writing.Used informally to request information. It can sound casual in context but is appropriate in most situations.

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Let me know
Tell me this

Frequently asked questions: Let me know vs Tell me this

What's the difference between Let me know and Tell me this?

Let me know: Tell me when you have information. Tell me this: Ask someone for information about something.

Which is more common: Let me know and Tell me this?

Let me know is the most common in everyday English.

Can you show an example of each?

Let me know: Please let me know if you can come to the party. Tell me this: Can you tell me this, how does it work?

Can I use Let me know and Tell me this interchangeably?

Not always. Let me know and Tell me this are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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