don't judge a book by its cover
Meaning
appearances can be misleading, so assess things properly
Usage frequency
Common · 17 corpus occurrences
Recorded for “You can't judge a book by its cover” in COCA, searched on 2016-02-22.
About these frequency groups
Groups use full-form occurrence counts in the Corpus of Contemporary American English (COCA), recorded in 2016–2017. For a proverb with several forms, we use the highest individual count, since adding overlapping forms could count the same occurrence twice.
These are historical American English corpus counts, not estimates of how often everyone uses a saying today. A zero means no full-form match was recorded. The source’s separate familiarity ratings are retained in the data but do not determine this ordering.
We grouped variants, merged reviewed duplicate entries, and preserved existing editorial wording. The source includes historical and dated sayings; inclusion is not an endorsement.
In a conversation
“The restaurant looks shabby, but don't judge a book by its cover — the food is excellent.”
When to use it
Use when first impressions give an unfair or incomplete picture of a person or thing.
The image behind the saying
A book's outer cover tells you little about the quality of its contents; people, like books, need to be looked at more closely.