can't say for sure

(I) can't say for sure

I don't know with certainty. A: "How many people are coming to dinner tonight?" B: "I can't say for sure—my family tends to just show up without responding to invitations."
See also: say, sure
Farlex Dictionary of Idioms.

(I) can't say for sure.

Inf. I do not know with any certainty. Tom: When will the next train come through? Jane: I can't say for sure. Bob: How can the driver hit so many potholes? Bill: Can't say for sure. I know he doesn't see too well, though.
See also: say, sure
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • (I) can't say for sure
  • (I) can't rightly say
  • can't rightly say
  • rightly
  • for sure
  • for certain
  • (I) can't say as I do(, can't say as I don't)
  • can't say as I do
  • (I) can't say as I do
  • (I) can't say's I do
References in periodicals archive
It's not clear whether the mini-brains are conscious -- the team behind the breakthrough suspect they're not but can't say for sure -- opening up a new ethical dimension to this area of research moving forward.
Well, we can't really say that the DDR has not prevented premature organ procurement (early grave robbing) but at the same time we can't say for sure that the rule has not contributed to the shortage of organs for donation.
He said at the launch of Leisureplex's 'Share Your Summer' campaign that they're striving for consistency and admitted: "I really can't say for sure why that inconsistency is there."
According to data compiled by Lori Lewis and Officially Chadd on Visual Capitalist, a single internet minute holds 1 million Facebook logins, 4.5 million videos watched on YouTube, 1.4 million swipes on Tinder (right or left, we can't say for sure), and a total of 41.6 million messages sent on WhatsApp and Facebook Messenger.
'We can't say for sure what happened to Lycha but we'll know after three weeks.'
"I don't think that it would have happened anyway, I can't say for sure. But without James it seems impossible."
We can't say for sure if Google has omitted Edge support on purpose.
So I can't say for sure that the eelworms you found were harmful.
"I can't say for sure what is happening, but we have the fewest officers since 1974 and that's having a knock-on effect."
"Although we can't say for sure that the growing use of smart phones caused the increase in mental health issues, that was by far the biggest change in teens' lives between 2010 and 2015," she further stated.
He says he can't say for sure whether the EU is going to reward this situation yet he hopes such a step will soon be taken.
Sam Delson, a spokesman for California's Office of Environmental Health Hazard Assessment was quoted saying by the (http://www.latimes.com/business/la-fi-roundup-california-20170314-story.html) LA times : "We can't say for sure. We're reviewing those comments.
He can't say for sure at this point whether Single and Sober (singleandsober.com) could become his main vocation someday.
He says that while watching the trailer he "felt like something had been taken away." He wrote: "In the case of Renee Zellweger, it may look to a great many people like something more than an elaborate make-up job has taken place, but we can't say for sure. What we can say is that if that happened, it reflects something indescribably sad about our culture." In response, McGowan wrote: "Zellweger is a human being, with feelings, with a life, with love and with triumphs and struggles, just like the rest of us.
She came out of the last race well, although I can't say for sure she's improved.