What is tougher about Hard?
Hard puzzles keep the same four rules, but with far fewer starting numbers. You will be leaning on the signs from the very first move, and the squares with no signs on them will mostly be solved last.
Do not rush. Most Hard Greater Than Sudoku puzzles take 15–30 minutes once you are used to them, and longer while you are still learning.
If you have not played the easier levels yet, do a few rounds at Medium Greater Than Sudoku first to make sure the basic strategies — the chain squeeze, clamping from both sides, hunting 1s and 9s — feel automatic. Hard relies on all of them at the same time.
Two real solver tricks
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Walk the whole chain
Do not stop at the two squares either side of a sign. Follow the arrows as far as they go in both directions, counting the steps. Every step above a square raises its smallest possible value by one; every step below lowers its largest.
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Naked pairs across a sign
If two squares in the same row, column or box can only be 3 or 5, no other square in that region can be 3 or 5 either. This is even more powerful here, because the signs have already trimmed the candidate lists down to size.
Hard puzzle game plan
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Step 1
Tap Auto Notes to fill in every candidate number.
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Step 2
Walk every chain of signs end to end and erase candidates that are out of range for their position.
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Step 3
Solve signed squares whenever you can — they unlock their sign AND their row, column and box all at once.
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Step 4
Hunt for naked pairs in rows, columns and boxes, especially the ones that a sign passes through.
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Step 5
When you are stuck, tap Hint — then keep going!
Common Hard mistakes
- ⏩ Going too fast. Hard punishes a quick guess — one wrong number ripples through a row, a column, a box AND a chain of signs.
- 🔄 Reading a sign backwards. The point aims at the smaller number, every single time. Tap a square to light up its signs if you are unsure.
- 📝 Forgetting to update notes after a placement. Always erase the new digit from the notes of its neighbours.
- 🔢 Only using row, column and box logic. The signs are there to be used.
- ✅ Skipping the Check button. If the puzzle feels stuck, the likeliest reason is a wrong digit from earlier.
Frequently asked questions
Is Hard too tough for kids?
Hard is really meant for kids who have already played a lot of regular sudoku and a few Easy and Medium Greater Than puzzles. If it feels too tough, jump back to Medium — there is no rush.
Can I solve a Hard Greater Than Sudoku without guessing?
Yes — every puzzle on this site has exactly one solution and is designed to be solved with logic. If you are stuck, the Hint button always reveals a correct square.
Why are there fewer signs on Hard than on Easy?
Because we remove every sign the puzzle can do without. On Easy we keep plenty of extra signs to help you; on Hard almost every sign that survives is one you genuinely need.
How does Hard compare to Hard classic 9×9?
They are different challenges. Hard 9×9 is all about pattern spotting; Hard Greater Than Sudoku adds chain-of-comparison thinking that classic sudoku does not have. Most kids who can do one can pick up the other within a few sessions.
Try other sudoku games
Different rules, same friendly board. Pick a sibling puzzle to play next.