Difference between big and large

I would say that "big" is a more casual and general term, while "large" is the word used when measuring.

For example, if you are cooking, you would look for two large eggs rather than two big eggs. Or when shopping for clothes, you would find Large sizes rather than Big sizes. Or when counting money, you might get a large sum instead of a big sum.

This is because "large" is a useful term for measuring quantities and numbers, while "big" can be used for more abstract items.

For instance, the child had big feelings, you can make a big decision, it's no big deal, etc. These items cannot be measured with numbers.

Separately, if you want to compare two things, one can equally be bigger or larger than the other.

While big and large often overlap, big is generally more common and flexible (big mistake, big day, big opportunity, etc), whereas large tends to sound more formal and is used more often with quantities, numbers, and measurements (large amount, large number, large population).

Yes. “Big” and “large” mean almost the same thing, but “big” is more informal and commonly used.

no.....but used interchangeably ....and mostly by custom