ICCF numeric notation

In ICCF numeric notation, each square of the chessboard has a two-digit designation.

[1] In numeric notation, each square is designated with a two-digit number via a coordinate system.

For promotion, a fifth digit is added to the move's notation: 1 for queen, 2 for rook, 3 for bishop, and 4 for knight.

A variant four-digit notation where the ending rank is omitted (because it is always 8 for White and 1 for Black) also exists (e.g. 6762); however, this is considered confusing and contradicts the standard.

German professor J. W. D. Wildt of Göttingen devised numeric notation circa 1803.