Text messages are limited to 160 GMS characters. If your text contains any Unicode(Non-English, international characters) symbols, it needs to encoded as Unicode which reduced the text character counts to 70 characters per text message instead of 160. This means that a 160-character SMS message will be split into three text messages if they have Unicode symbols. This is not a user-friendly and can cost your three times cost to send one text message. By using the Unicode character detection tool, you can identify and replace symbols that aren't part of the 7-bit GSM charset to avoid extra cost. We also provide a transliterate of the text message to GSM characters, which might not exactly same as your original text with but will be a new version of replacement characters from GSM character set, without any Unicode.
You can always access Unicode detection tool from Tools Menu option from Dashboard.