Definition of you can't judge a book by its cover in English:

you can't judge a book by its cover

phrase

proverb
  • Outward appearances are not a reliable indication of the true character of someone or something.

    • ‘Despite the admonition that you can't judge a book by its cover, I tend to find that, increasingly, you can.’
    • ‘I told you that you can't judge a book by its cover,’ he reminded her, in an ‘I-told-you-so’ type of manner.’
    • ‘Guess you can't judge a book by its cover after all.’
    • ‘Mind you, you can't judge a book by its cover, me old mum used to say.’
    • ‘They seemed all right at first but I suppose you can't judge a book by its cover.’
    • ‘This was just another thing that contributed to the fact you can't judge a book by its cover.’
    • ‘Anyone who says you can't judge a book by its cover is an idiot.’
    • ‘And I think that, like this movie says, you can't judge a book by its cover.’
    • ‘This book defies the old adage that claims you can't judge a book by its cover.’
    • ‘But you can't judge a book by its cover or whatever they say.’