Daily Even Odd Sudoku
The extra rule
Shaded squares hold an even digit. Circled cells hold an odd one.
A grey square means the digit there is one of 2, 4, 6 or 8. A circle means it is one of 1, 3, 5, 7 or 9. Unmarked cells could be either.
Parity is a blunt tool and a powerful one. There are only four even digits and five odd ones, so a row with four shaded cells has already told you a great deal before you place anything.
Controls
Click a cell and type a digit, or use the pad. Space toggles pencil marks. Arrow keys move. Progress saves in this browser as you go, so you can come back to the same puzzle later today.
Solvable Without Guessing
Every puzzle here was generated and then handed to a solver that is only allowed techniques a person can use. If it could not finish the grid without a guess, the puzzle was thrown away rather than published. That also makes the answer unique, because every digit it placed was forced.
More to Play
There is also a kropki sudoku, a xv sudoku, a greater than sudoku, a nonogram with hand drawn pictures, and 2048. All of them are on the games page, and the solvers for real objects are on the puzzle tools page.