Very Hard Sudoku Puzzles

If Hard Sudoku Puzzles no longer challenge you and you’re ready to take your skills to the next level, it’s time to tackle Very Hard Sudoku Puzzles. At this level, simple scanning and elimination won’t be enough—you’ll need to apply advanced techniques and plan your moves strategically.

Puzzles at this difficulty contain significantly fewer clues, meaning every solution requires deeper analysis and precise forward-thinking. This is a true test of logical reasoning for those seeking more demanding challenges.

On this page, you’ll find 2,000 of the most played Very Hard Sudoku puzzles. Out of millions of available grids, these have been the top choices among players looking for a true challenge. Each puzzle requires logical precision, strategic thinking, and advanced solving techniques. If you can master them, you’re one step away from reaching an expert level.

What Makes the Very Hard Level Stand Out?

• A highly limited number of starting clues, requiring more complex solving methods.

• The need for advanced strategies, such as multi-step eliminations and logical chains.

• Ideal for players who have mastered Hard Sudoku and want to reach a higher level of expertise.

How to Solve Very Hard Sudoku Puzzles?

At the Very Hard Sudoku Puzzles level, most basic solving methods become insufficient, requiring deep logical analysis to uncover solutions. While techniques from previous levels—such as XYZ-Wing, Skyscraper, and Chain Forcing—are still useful, additional highly advanced strategies are often necessary to eliminate incorrect values in the most complex grid structures.

1. Using the “Almost Locked Sets (ALS)” Method

The Almost Locked Sets (ALS) technique is an advanced elimination strategy that analyzes groups of cells containing a limited set of candidates. If a group of cells shares a unique set of numbers and is logically connected to other cells, certain digits can be eliminated. Follow these steps:

➡ Identify a group of cells (an Almost Locked Set) that contains a small set of candidates, but is not yet fully resolved.

➡ Check if this set is linked to other cells in a way that allows for the elimination of certain numbers elsewhere on the grid.

➡ Remove numbers that lead to logical contradictions and use the new information to advance your solution.

Example:

If three cells in one block contain the candidates 2, 4, and 7, and another set of cells in a different block can only contain 2 and 4, then 7 must be placed in one of the first block’s cells, allowing you to eliminate 2 and 4 from other locations.

2. Applying the “Nishio” Technique

The Nishio technique is a more advanced version of forcing chains, based on a trial-and-error approach where one candidate is temporarily assigned, and the outcome is tested for contradictions. Follow these steps:

➡ Choose a cell with exactly two possible numbers.

➡ Assume the first number is correct and check if this leads to a scenario where another row, column, or block becomes unsolvable.

➡ If it does, then the assumption was incorrect, and the second number must be the correct choice.

Example:

If a cell can contain 5 or 8, but placing 5 results in a conflict elsewhere, then 8 must be the correct value.

3. Using the “Grouped X-Cycles” Method

The Grouped X-Cycles technique is an extension of X-Wing, but instead of analyzing individual cells, it examines groups of candidates across different rows and columns. This method allows for advanced logical eliminations across the grid. Follow these steps:

➡ Identify a number that can only appear in specific groups of cells across multiple rows or columns.

➡ Check if these groups form a logical chain, allowing for the elimination of that number in other locations.

➡ If the chain holds, remove the incorrect candidates and use this information to progress in solving the puzzle.

Example:

If 9 can only be placed in specific groups of cells in rows 2 and 7, and these groups create a logical dependency, then 9 can be removed from other locations in the same columns, simplifying the grid.

At the Very Hard Sudoku Puzzles level, standard elimination techniques are often not enough, and solutions require multi-step reasoning across multiple linked cells. Strategies like Almost Locked Sets, Nishio, and Grouped X-Cycles can greatly enhance your ability to solve even the most complex Sudoku puzzles.

What’s Next? Try Extremely Difficult Sudoku Puzzles

If Very Hard Sudoku is no longer enough and you’re looking for an even greater challenge, try Extremely Difficult Sudoku Puzzles. At this stage, you’ll encounter puzzles that require multi-step analysis and mastery of the most advanced logical strategies.

Choose a puzzle and see if you’re ready for this challenge!