I have a huge cell containing text which is without line breaks. Once I need to copy&paste it I use online auto line breaker tool which makes new break lines every X characters.
I'm looking for solution how to make this work in Excel.
This may not be practical, depending upon how often required and how many cells are to be split by line at a time, but most things possible with VBA are also possible without, even if impractical.
Assuming your text is in B1 and the requisite character limit in A1. In C1:
=MID($B1,1+$A1*(COLUMN()-3),$A1)
copied across to D1. In C2 =C1
, in D2:
=C2&CHAR(10)&D1
then copy D1:D2 across until first blank shows up in Row1 (assumes you won't have a multitude of consecutive space 'characters').
The result should be below the last non-blank cell in Row1.