In Sublime Text 3, unicode characters are not shown correctly. In gedit it works fine. I tried saving the document as UTF-8, Tried setting default encoding to UTF-8 but stil
Sublime Text 3 should support many utf-8 locales now.
If Xuwei Khan's answer doesn't work for you, then use this command:
iconv -f Windows-1253 -t utf-8 input.txt > output.txt
Or replace Windows-1253 with an an other iso locale suitable for your language needs.
Windows-1253