Always better to ask!
If you have a rooster with hens, chances are the majority of the eggs are going to be fertile.
Fertile eggs don't develop into embryos until they've been incubates around 100 degrees for a couple of days. If you collect your eggs every day, or even every other day, you will simply have good, fresh eggs. I've kept roosters with my layer flock for 20+ years, and never once have I had a nasty surprise when I cracked an egg, collecting that often. Even when my coop gets over a hundred degrees, I've had eggs there 2 days with no issues.
It is possible to tell the difference between a fertile and non-fertile egg once you crack the egg, but it takes a very practiced eye. Nothing obvious at all, and you'll never ever notice the difference.
Some of the "free range organic" type eggs sold at stores are fertile. There's a whole thread here about folks incubating eggs from Trader Joe's and similar stores. So, if you've been trying to buy better quality eggs for your family, chances are they've already been eating fertile eggs
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I've stored my fertile eggs on the counter in my un-climate controlled kitchen for weeks. Again, never once have I had anything icky when I've cracked an egg besides the occasional meat spot, which has nothing to do with fertilization.