To get the value of character under cursor: ga (where ^V means "hit Ctrl-V, except if you use Ctrl-V to paste, in which case you should hit Ctrl-Q instead): By decimal value: ^Vnnn (with 000 <= nnn <= 255) By octal value: ^VOnnn or ^Vonnn (with 000 <= nnn <= 377) By hex value: ^VXnn or ^Vxnn (with 00 <= nn <= FF) By hex value for BMP Unicode codepoints: ^Vunnnn (with 0000 <= nnnn <= FFFF) By hex value for any Unicode codepoint: ^VUnnnnnnnn (with 00000000 <= nnnnnnnn <= 7FFFFFFF) Notes: - This works on the command line (e.g. when entering a pattern/regular expression) too. - In all cases, initial zeros may be omitted if the next character typed is not a digit in the given base (except, of course, that the value zero must be entered as at least one zero). - Hex digits A-F, when used, can be typed in upper or lower case, or even in any mixture of them. To search & replace: Check the help for \%u: /\%d /\%x /\%o /\%u /\%U E678 \%d123 Matches the character specified with a decimal number. Must be followed by a non-digit. \%o40 Matches the character specified with an octal number up to 0377. Numbers below 040 must be followed by a non-octal digit or a non-digit. \%x2a Matches the character specified with up to two hexadecimal characters. \%u20AC Matches the character specified with up to four hexadecimal characters. \%U1234abcd Matches the character specified with up to eight hexadecimal characters.