proof of the pudding

American  

[proof uhv thuh pood-ing] / ˈpruf ʌv ðə ˈpʊd ɪŋ /

noun

1. the true value or quality of something, as seen when it is experienced, tried, or put to use.

   The proof of the pudding for a business is what customers say about it.

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Etymology

Origin of proof of the pudding

First recorded in 1600–20; from the proverb “The proof (i.e., test) of the pudding is in the eating”

Example Sentences

The proof of the pudding will be in the eating.

From BBC

In other words, the proof of the pudding will be in the eating.

From BBC

“The proof of the pudding will be what happens when it goes into humans and how going into a preimmune population skews the response to it,” Dr. Webby said.

From New York Times

"The final proof of the pudding is the ship's performance during sea trials. While it seems to be behaving pretty well, stability wise, aircraft operations have yet to commence. One hopes it will be a success story all the way," former Chief of India's Naval Staff Admiral Arun Prakash told Reuters.

From Reuters

"The critical sign of seriousness is complete Zambia, complete Chad, complete Ethiopia - it is the very old saying: the proof of the pudding is in the eating."

From Reuters