CLEAN

The CLEAN function removes most common nonprinting characters (Unicode character codes 0–31) from text.

CLEAN(text)

text: Any value from which you want to remove nonprinting characters.

Notes

Example

Suppose you copy what you believe to be the text “a b c d e f” from another application and paste it into cell A1, but instead see “a b c ? ?d e f”.  You can try using CLEAN to remove the unexpected characters:

=CLEAN(A1) returns “a b c d e f”.

See also
SUBSTITUTE
TRIM