Roughly speaking, each character in a text file adds one byte to a file’s size.

Space & Newline also considered as character.

For example, the size of following files is 10 bytes.

a b c dd e

For example, a file containing 52,428,800 characters takes up 5,242,8800/ 1,024 2 = 50 mebibytes , or 50 MiB on disk.