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Medium · LDI v0

Play Medium Sudoku Online

Choose from three calibrated medium puzzles. New Game stays on Medium, and the verified puzzle facts update with the board.

LDI v0

Verified puzzle facts

Puzzle ID
LDI0-020a16dfa63d6d2cf42de1e946495f4d99bc3955
Difficulty model
LDI v0
LDI score (0–100)
15
Clue count
26
Logical steps
55
Hardest technique
Hidden Single

Clue count is a board fact, not the difficulty verdict. The tier comes from this published LDI version.

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What Medium feels like

The same core logic now takes more patient, repeated scanning.

The current Medium catalogue still resolves with singles, but its verified LDI scores are higher than Easy. Fewer placements appear on the first pass, so each result must trigger a careful rescan of its row, column, and box.

How to approach Medium

Use short candidate lists to reveal less obvious singles.

After each placement, update only the affected row, column, and box, then look for a number that can occupy just one square in that unit. Notes preserve the comparison, so you can resume the scan without rebuilding every candidate.

Next step

Want deductions that span more of the grid?

Move to Hard when repeated rescans and less visible hidden singles feel comfortable, and you want a larger verified logical workload.

Try Hard Sudoku

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Medium Daily Sudoku challenges

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Why this tier

Medium puzzles require more logical work than the Easy tier.

The LDI score combines the proof-checked techniques and logical steps required by the puzzle shown on the board.

Read the LDI method

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