X-Sudoku (PuzzleMadness)
Sudoku where both long diagonals must also hold 1 to 9, new each day.
Every day: A new dated X-Sudoku puzzle every day, the same for every player, one for each difficulty (Easy, Medium, Hard, Tough and Mixed); completed puzzles score on monthly and all-time leaderboards and past days stay in the archive. New puzzle: Once a day (the site does not state the time).

PuzzleMadness posts a new X-Sudoku puzzle every day, the same grid for every player, at several difficulty levels. Normal sudoku rules, plus both main diagonals must contain the digits 1 to 9 once each. Finished puzzles score points on the site's monthly and all-time leaderboards.
About X-Sudoku (PuzzleMadness)
X-Sudoku is a classic 9x9 sudoku with one extra rule: the two long diagonals, corner to corner, must each hold 1 to 9 once, just like a row or column. The diagonals give extra information, so a square on a diagonal often has fewer candidates than it would in a plain grid.
The daily page opens today's puzzle on its own, and its title carries the date (on 3 October 2026 it read "Daily Medium X-Sudoku Puzzle for Saturday 3rd October 2026 (Medium)"). There is a separate dated puzzle for each difficulty: Easy, Medium, Hard, Tough and Mixed. Past days stay in the archive, so a missed puzzle can be played later, and there is a print version and an image download of the grid. PuzzleMadness does not publish solutions: the site tells you when you have finished a grid correctly or made a mistake. Each completed puzzle adds to your total on the X-Sudoku monthly and all-time leaderboards, where only your best score on any one puzzle counts.
Remember the centre square sits on both diagonals and in the middle row, column and box at once, so it is one of the most constrained squares in the grid. Otherwise solve as usual and check the diagonals whenever a square on them gets down to two candidates.
PuzzleMadness is a British puzzle site with dozens of daily puzzle types in the browser, from many sudoku variants to logic grids such as Nurikabe, Hashi and Slitherlink. It is free to play and carries ads. A free account keeps track of the puzzles you have finished and puts your name on the leaderboards, and the badges next to usernames mark how many puzzles a player has completed.
How to play X-Sudoku (PuzzleMadness)
- Open the day's X-Sudoku page and choose Easy, Medium, Hard, Tough or Mixed.
- Fill digits so every row, column and 3x3 box holds 1 to 9 once.
- Also make both shaded diagonals hold 1 to 9 once.
- Complete the grid; the site confirms the solve and records your score.
Tips
- Check each diagonal for digits it is missing, the same way you would scan a row.
- The centre square belongs to five units at once; it is often an early placement.
- Squares on a diagonal near the corners also share a box with the other diagonal's ends.
Questions
What is the extra rule in X-Sudoku?
Both main diagonals must contain the digits 1 to 9 once each, on top of the usual row, column and box rules.
When does the PuzzleMadness X-Sudoku change?
Once a day: each puzzle is dated, and the daily page opens the current day's grid. The site does not say at what time the new one appears.
Is PuzzleMadness X-Sudoku free?
Yes. You can play without an account; the site shows ads. A free account records which puzzles you have finished and enters your scores on the leaderboards.
Where can I find the answers?
PuzzleMadness does not publish solutions. It tells you when your grid is complete and correct, and when you have made a mistake.
Can I play earlier X-Sudoku puzzles?
Yes, older puzzles are in the archive, and puzzles completed on any day count toward that month's leaderboard.
Games like X-Sudoku (PuzzleMadness)

Diag (Mind Loft)
Mind Loft's daily Sudoku X with the same diagonal rule

The Daily Sudoku X (SudokuWiki)
SudokuWiki's daily Sudoku X

Sudoku X (Daily Mail)
The Daily Mail's Sudoku X

Sudoku (PuzzleMadness)
The plain 9x9 sudoku from the same site, with its own daily grids and leaderboard

Jigsaw Sudoku (PuzzleMadness)
Another PuzzleMadness sudoku, with crooked regions instead of 3x3 boxes

12x12 Giant Sudoku (PuzzleMadness)
A 12x12 sudoku using 1 to 9 and A to C, one new grid a day.

16x16 Giant Sudoku (PuzzleMadness)
A 16x16 sudoku using 1 to 9 and A to G, one new giant grid a day.

Arrow Sudoku (PuzzleMadness)
Sudoku with arrows: the circled digit equals the sum along its stalk.