Sudoku

How to play

1. Select an editable cell, then choose a digit from the number buttons or type it. Arrow keys move the selection; Erase, Backspace, or Delete clears it.
2. Turn Notes on (or press N while on the board) to save possible digits in a cell. Choose a note again to remove it. Entering a number clears that cell's notes and removes that digit from related row, column, and box notes.
3. Given digits stay fixed. Repeating a digit in a row, column, or box is rejected without changing your saved board.
4. An accepted entry is not a hint that the digit is correct. The puzzle completes when the entire grid is correct.

Daily challenge

Everyone gets the same daily challenge for the UTC date. Your saved attempt resumes when you return; the next challenge arrives at midnight UTC. Daily results do not change Elo.