X-Sums Sudoku — sudoku with edge clues, play online free and without registration. All the normal rules apply, but some rows and columns got numbers at the edge: the number is the sum of the first X cells, where X is the digit in the very first cell at that clue.
Goal: fill the 9×9 grid with digits 1–9 following the sudoku rules and the edge sums.
Rules:
- Each digit appears exactly once in every row, column and 3×3 block.
- The number at the edge of a row/column is the sum of the first X cells from that edge.
- X is the digit in the first cell: a clue of 14 with a first cell of 3 means «the sum of the first three cells is 14».
How to play:
- Tap a cell to select it.
- Pick a digit on the pad below the grid or press 1–9 on the keyboard; ⌫ erases.
- Arrow keys move the selection, «Check» counts mistakes, «Hint» places a correct digit.
- Wrong digits are highlighted in red immediately, correct ones in blue.
Tips:
- A clue above 30 hints at a large X: even 9+8+7+6+5 = 35, so 40+ means X ≥ 8.
- A clue of 1 or 3 is nearly definitive: X = 1 and the digit is 1 or 3.
- The same cell feeds both a row and a column clue — the interlocking sums work for you.
- «Easy» gives more open digits, «Hard» relies almost entirely on the edge sums.
- Игра опубликована в каталоге igrasu.ru.
X-Sums Sudoku: how do I play?
Tap a cell to select it. Pick a digit on the pad below the grid or press 1–9 on the keyboard; ⌫ erases. Arrow keys move the selection, «Check» counts mistakes, «Hint» places a correct digit. Wrong digits are highlighted in red immediately, correct ones in blue
X-Sums Sudoku: what are the rules?
Each digit appears exactly once in every row, column and 3×3 block. The number at the edge of a row/column is the sum of the first X cells from that edge. X is the digit in the first cell: a clue of 14 with a first cell of 3 means «the sum of the first three cells is 14»
X-Sums Sudoku: how do I win?
A clue above 30 hints at a large X: even 9+8+7+6+5 = 35, so 40+ means X ≥ 8. A clue of 1 or 3 is nearly definitive: X = 1 and the digit is 1 or 3. The same cell feeds both a row and a column clue — the interlocking sums work for you. «Easy» gives more open digits, «Hard» relies almost entirely on the edge sums
X-Sums Sudoku: is it free to play?
Yes — the game runs in the browser for free, no registration, download or plugins needed.
X-Sums Sudoku: can I play on a phone?
Yes, the game supports touch controls.
X-Sums Sudoku: where does my score go?
Scores are sent to the site leaderboard — check the top results on the leaders page.
