(you) could have fooled me

(you) could have fooled me

Really? I thought the opposite was true. A: "This neighborhood has really improved in recent years—it's quite popular now." B: "Wow. With all the boarded-up buildings, you could have fooled me." Maria is shy? Could have fooled me. She was talking all night. You two are fighting? You could have fooled me—I didn't pick up on any tension at last night's party.
See also: could, fool, have
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

(You) could have fooled me.

Inf. I would have thought otherwise.; I would have thought the opposite. Henry: Did you know that this land is among the most productive in the entire state? Jane: You could have fooled me. It looks quite barren. John: I really do like Mary. Andy: Could have fooled me. You treat her rather badly sometimes.
See also: could, fool, have
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

you could have fooled me

People say you could have fooled me to show that it does not seem to you that something is true. `I came here to apologize.' — `You could have fooled me.' Car makers are supposed to be bringing their prices down. Well, you could have fooled me.
See also: could, fool, have
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

you could have fooled me!

used to express cynicism or doubt about an assertion. informal
See also: could, fool, have
Farlex Partner Idioms Dictionary © Farlex 2017

you could have ˌfooled ˈme!

(informal) used for expressing your surprise about a statement, claim, etc: ‘He’s quite intelligent, you know.’ ‘You could have fooled me! I’ve never heard him say anything intelligent at all.’
See also: could, fool, have
Farlex Partner Idioms Dictionary © Farlex 2017
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