sure as eggs is eggs

(as) sure as eggs (is eggs)

A phrase used to describe something that is definitely going to happen. It might be a corruption of the phrase "as sure as x is x." Of course I'll be there, sure as eggs is eggs!
See also: egg, sure
Farlex Dictionary of Idioms.

sure as eggs is eggs

or

sure as eggs

BRITISH, INFORMAL
If you say that something will happen as sure as eggs is eggs or sure as eggs, you mean it will certainly happen. He'll be back, asking for more money. Sure as eggs is eggs. If you don't deal with the problem now, then sure as eggs you'll have cause to regret it later. Note: This expression may be a variation or mishearing of `as sure as x is x', referring to the use of x to represent a variable in algebra and logic.
See also: egg, sure
Collins COBUILD Idioms Dictionary, 3rd ed.

sure as eggs is eggs (also sure as fate)

without any doubt; absolutely certain.
See also: egg, sure
Farlex Partner Idioms Dictionary

(as) sure as eggs is ˈeggs

(old-fashioned, British English, informal) absolutely certain; without any doubt: If he goes on driving at that speed, he’ll end up in hospital, as sure as eggs is eggs.
See also: egg, sure
Farlex Partner Idioms Dictionary
See also:
  • (as) sure as eggs (is eggs)
  • eggs is eggs
  • 57
  • Heinz
  • Heinz 57
  • Heinz 57 (variety)
  • Heinz 57 variety
  • how about
  • how/what about...?
  • fosho