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Sudoku Puzzles

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Pro Tip

Start by finding boxes, rows, or columns that already have 7–8 digits filled — the 9th is trivial. Look for digits that appear frequently in the given cells to quickly eliminate possibilities.

Difficulty:Intermediate

Did you know?

Sudoku was invented by American architect Howard Garns in 1979 (as 'Number Place') and popularized in Japan in 1986 by Maki Kaji, who named it 'Sudoku' (a Japanese abbreviation of 'the digits must remain single'). It went global after appearing in British newspapers in 2004.

Mathematically verified
Reviewed May 2026
Used 13K+ times
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