Position Editor
Pieces
Pick a piece, then tap a square to place it. Tap it again to take it off.
Side to move
Castling rights
FEN
Pick a piece, then tap a square to place it. Tap it again to take it off.
The Position Editor builds any chess position by hand. Pick a piece from the palette beside the board and tap a square to place it. Tap the same square again to take it off, or pick Erase to clear any square. As you go, the FEN for the position is written out underneath, ready to copy. It is free and needs no account.
A position is more than where the pieces stand. Set whose turn it is, tick the castling rights each side still has (White O-O, White O-O-O, Black O-O, Black O-O-O), and enter an en passant square such as e3 or d6 if a pawn has just moved two squares. All of it goes into the FEN, so the position you hand to an engine is the position you meant.
Starting position puts every piece back on its opening square, and Empty the board clears it so you can build an endgame or a puzzle from nothing. If you already have a FEN, paste it and press Load to put that position on the board and edit from there.
An editor spends most of its time on positions that are not legal yet, so this one lets you place anything, then says what is wrong before you send it anywhere. It checks that each side has exactly one king, that no pawn stands on the first or last rank, and that the side not to move is not already in check. Until the position passes, the links to the engine stay switched off and the reason is shown under the board.
FEN is the standard one-line way to write down a chess position. It lists the pieces rank by rank from White's back rank upwards, then who is to move, the castling rights, the en passant square, and two move counters. Almost every chess site and engine reads it, which is why it is the easiest way to move a position from one tool to another.
Once the position is legal, Analyse on the board sends it to the Analysis Board, where Stockfish 18 evaluates it and you can play it out. Find the best move sends it to the Best Move Finder for a single answer.
Pick a piece from the palette and tap the square you want it on. Tap it again to remove it, then set the side to move and the castling rights.
Build the position and the FEN is written out under the board as you go. Press Copy to copy it.
Yes. Paste it into the FEN box and press Load, and the position appears on the board ready to edit.
The position is not legal yet. The editor shows why: a side without exactly one king, a pawn on the first or last rank, or the side not to move already in check.
Yes, with no account needed.