your guess is as good as mine

US /jʊər ɡɛs ɪz æz ɡʊd æz maɪn/
UK /jʊər ɡɛs ɪz æz ɡʊd æz maɪn/
"your guess is as good as mine" picture
1.

votre supposition est aussi bonne que la mienne, je n'en sais pas plus que vous

used to say that you do not know the answer to a question, or do not know what is happening, for the same reason as the person asking

:
Why did he leave so suddenly? Your guess is as good as mine.
Pourquoi est-il parti si soudainement ? Votre supposition est aussi bonne que la mienne.
When will the new policy be implemented? Your guess is as good as mine.
Quand la nouvelle politique sera-t-elle mise en œuvre ? Votre supposition est aussi bonne que la mienne.