Refers to any person or people without specifying who
Examples:
Any one can learn to play the guitar with practice.Is there any one who knows how to solve this issue?If any one wants to join, let me know by tomorrow.
Synonyms:
Antonyms:
Anyone
/ˈeniwʌn/
An unspecified person or people, used when it does not matter who
Examples:
How can anyone think this is justice?There's nothing anyone can do about it now.Never judge anyone by another's opinions.
Synonyms:
Antonyms:
Ways to tell them apart:
Any one is a phrase that refers to a specific person or thing within a group when paired with of.
Anyone is a single word and refers to any person at all, without specifying a group.
If you can mentally replace it with any one person and it makes sense, then anyone is likely correct.
When you are emphasizing a specific choice among many, use any one.
Try breaking the word apart: if the sentence still makes sense using any one, then use the two-word form.