# Is "Rdxd2" algebraic chess notation valid?

Is the algebraic notation `Rdxd2` valid?

If there is a problem with this notation, then how can it be corrected?

• Even "R2d2" could be valid :-) Commented Mar 18, 2021 at 1:19

If you have two rooks, standing on different files (one of them on the `d`-file), that could capture on `d2`, then `Rdxd2` is the correct notation.

If you have two rooks on the `d`-file, and both can take on `d2`, then use the rank number to disambiguate, for instance `R1xd2`.

This is according to the Algebraic System required by FIDE's Laws of Chess (see appendix C, paragraph C.10).

In the very, very rare case that you have more than two pieces of the same kind that can capture on the same square, it might be necessary to use both rank and file to disambiguate. This could theoretically be needed for queens, bishops and knights, but never for rooks. As Martin Bonner explains in the comments, for this to be necessary you would need to have a piece which is on the same rank as another of the same kind and the same file as a third of the same kind, and all three attack the same square. That is not possible with rooks.

• That will never be necessary with rooks; it can only happen with queens. E.g. with queens on a1, b1 and a2, Qa1xb2 is the same move in short and in long algebraic notation. Commented Mar 17, 2017 at 8:27
• @Glorfindel I guess it could also happen with knights or bishops. Commented Mar 17, 2017 at 8:38
• Ah, of course, you're right. I meant that I have only seen it happen with queens. Commented Mar 17, 2017 at 8:38
• @MartinBonner True, but in your example you only need rank or file to disambiguate, you don't need both for the same move: `R1xd2`, `R3xd2`, `Rcxd2`, `Rexd2`. Commented Mar 17, 2017 at 13:42
• Ah yes, of course. You need to have a piece which is on the same rank as another and the same file as a third, and all three can attack a square - and that is not possible with rooks. Commented Mar 17, 2017 at 13:54

There is no problem with this notation . Chess Board is divided into 1-8 ranks and a-h files .

When a Rook standing on different ranks and have one common attacking Square or same Piece then we use R(1-8) * Square number . eg of such moves are R7e3,R2e3 .

When Rook standing on different Files and have one common attacking Square or same Piece then we use R(a-h) * Square number. eg of such common moves when we are almost completing the Development Rad1,Rfe1.

You may even remove the asterisk in both cases .

• -1 It is an “x”, not an asterisk. I have never seen an asterisk used in chess notation. This answer is difficult to read. This is partly because of the broken English, but also because of this phrase: “have one common attacking Square or same Piece”. What does this mean? Commented Mar 14, 2021 at 9:48

If this notation is needed to differentiate between 2 rooks on the "d" file, then it is valid, If there's only one rook on the "d" file, it's not invalid, but redundant.

• Just out of perversity, you might have promoted two pawns to Rooks so that you now have four of the things, placed on d8,d1,a2,h2, and if one of them captures on d2 you will need to specify both rank and file. Well, I thought was funny Commented Jun 4, 2017 at 22:18
• @PhilipRoe No. (Although the same perverse thinking led me to search for this question) In your example, Rd8xd2 = R8xd2, Rd1xd2 = R1xd2, Ra2xd2 = Raxd2, Rh2xd2 = Rhxd2. In fact, the necessity for "full specification" is only possible with Queens, Knights, or Bishops. See the comment thread in the accepted answer. Commented Mar 1, 2021 at 21:59
• -1 This answer has it backwards. If there is only one rook on the d-file (but there is also a rook on the second rank that can capture on d2), that is precisely when this notation should be used. This notation cannot differentiate between two rooks on the d-file; this requires a rank. Commented Mar 14, 2021 at 9:51