know like the back of one's hand
In real, traceable use. Part of the curated seed collection; community review is coming.
Meaning · English
To be intimately knowledgeable about something.
Where it’s used:
Used
American English
Examples
He knows the software like the back of his hand, and can often solve problems over the phone, without looking.
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “know like the back of one's hand” mean?
To be intimately knowledgeable about something.
Is “know like the back of one's hand” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.