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Latest Very Difficult Sudoku Puzzles - Updated list - 7Sudoku
www.7sudoku.com
All the puzzles in this page are rated very difficult. Very Difficult Sudoku Puzzles very difficult. sudoku puzzle published on 2021/11/22 sudoku puzzle ...
Sudoku Puzzles: Hard - MathSphere
www.mathsphere.co.uk
The aim of a Sudoku puzzle is to fill in the grid so that each row, each column and each box contains all the numbers from 1 to 9. Usually the grid is 9 by 9,.
Hard sudoku puzzles online - solve difficult web sudoku for free
sudoku.com
Play hard level Sudoku online on Sudoku.com. Our daily difficult web sudoku puzzles are suitable for people, who possess an excellent knowledge of sudoku ...
Sudoku - Hard
www.dadsworksheets.com
These hard sudoku puzzles have fewer clues than the others on the site and ... Each puzzle page is part of a printable PDF with an answer key to help when ...
Hard Level - 27 Givens - Step-by-Step Solution - Web Sudoku
www.websudoku.com
Every Sudoku puzzle we provide comes with its step-by-step solution, such as the hard example shown below. The step-by-step shows one way to solve puzzle using ...
Extreme Sudoku - Hard and Difficult Printable Sudoku Puzzles ...
www.extremesudoku.info
Difficulty depends on the type of steps required to solve them, and also on the number of each type of step. See our guide to solution rules for hard sudoku ...
Sudoku Hard Strategy and Techniques level 4 game 1
suresolv.com
Hard fourth level Sudoku puzzle 1, Strategies Techniques and Solution. Submitted by Atanu Chaudhuri on Thu, 16/04/2020 - 01:07. Sudoku hard Strategy and ...
Sudoku Solving Techniques - Kristanix Games
www.kristanix.com
Solving a hard Sudoku puzzle will require quite a different set of techniques compared to an easy one. This article presents nine such techniques; ...
100 Free Printable Sudoku Puzzles - Memory Improvement Tips
www.memory-improvement-tips.com
There is a link to the Solutions on the puzzle page as well. The printable sudoku puzzles pages below are listed in order of difficulty.
Example Puzzles and Solutions
sandiway.arizona.edu
Difficult · Vegard Hanssen puzzle 2155141 · Challenge 2 from Sudoku Solver by Logic ...
Hard Sudoku Puzzles
www.sudoku.ws
Hard Sudoku Puzzles. Play an interactive sudoku, or try one of our printable hard sudokus. Hard Sudoku Puzzle 1 · Hard Sudoku Puzzle 2
Sudoku - The New York Times
www.nytimes.com
Default Difficulty. This is the difficulty that will be automatically selected when you first visit Sudoku. Easy Medium Hard ...
How To Use Sudoku XY-Wing To Solve Difficult Sudoku
www.sudokuessentials.com
Your ability to identify and solve this pattern will often break the logjam and lead you to the solution of a challenging Sudoku game.
What is the toughest sudoku in world? - Quora
www.quora.com
Originally Answered: What is the hardest sudoku puzzle ever created? And what makes it so difficult? According to Finnish mathematician Arto Inkala, ...
Sudoku techniques - Conceptis Puzzles
www.conceptispuzzles.com
The scanning technique is also very useful for hard puzzles up to the point where no further progress can be made and more advanced solving techniques are ...
Printable Sudoku Logic Puzzles
www.puzzlesandbrains.com
Printable Sudoku logic puzzles for kids and adults with answers in 6 by 6 and 9 ny ... We offer puzzles in 2 formats: 6 by 6 and 9 by 9, and in 4 difficulty ...
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION
www.amazon.com
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION: VERY LARGE PRINT (65pt font) - One Puzzle per page [CRAFTERS, SUDOKU] on Amazon.com.
Sudoku Solutions - Solver And Helper | Play Thousands Of ...
www.sudoku-solutions.com
The solver provides several analysis features which allow you to check if a puzzle is valid, rate the difficulty of a puzzle or get hints on how to solve a ...
Free daily Sudoku games from the Los Angeles Times
www.latimes.com
Check back each day for a new puzzle or explore ones we recently published. Back to all games→. Choose a difficulty level:.
The Miracle Sudoku May Be the Hardest Puzzle Ever
www.popularmechanics.com
The Miracle Sudoku adds challenging chess-themed restrictions to an almost empty grid. · Even easy sudoku grids require deductive reasoning, but ...
Guide to solving a hard, challenging Sudoku puzzle
www.sudokudragon.com
Using advanced strategies to solve a challenging puzzle solution step-by-step. a, b, c, d, e, f, g, h, i. A ...
How to Solve Sudoku Puzzles of Any Difficulty - The Habitat
thehabitat.com
This allows them to visit other boxes while remembering what their answers could be. It also enables many of the more complex Sudoku ...
Sudoku Difficulty
www.sudokuoftheday.com
How do we rank the difficulty of Sudoku puzzles? ... The higher the total cost, adding up over the whole solution, the harder the puzzle!
Extremely Hard Sudoku Puzzles for Experts
sudoku9x9.com
Play extremely hard Sudoku puzzles in our expert area. Be prepared to spend time on these crazily tough puzzles.
Advanced Sudoku Solving Techniques and Tips
sudokusolver.com
So, as we increase the difficulty Super Fiendish, the time has come to present the essential techniques for solving the most difficult Sudoku puzzles.
Hard Sudoku puzzles
images.template.net
Hard Sudoku by www.sudokupuzzle.org. Answers. Sudoku #1. 6. 2. 8. 5. 3. 4. 1 ... Hard Sudoku by www.sudokupuzzle.org. Answers. Sudoku #5. 8. 7. 6. 4. 3. 1.
FREE Printable Sudoku Puzzles
www.puzzles.ca
Sudoku puzzles to print and solve. Two per page. Three levels of difficulty: easy, medium, hard.
Hard Sudoku Puzzles for Kids - Free Printable Worksheets
www.kidsmathgamesonline.com
Check out our hard sudoku worksheets for kids and enjoy a range of free printable puzzles. Challenge students with some difficult sudoku puzzles that are ...
9x9 Sudoku Puzzles
www.sudoku-download.net
The Sudokus are offered in different difficulty levels and they have all different solutions. So if you solved the easy puzzles, you can download the medium or ...
Tough Sudoku Puzzles by Krazydad, Volume 1
krazydad.com
Each of my books contains a collection of eight sudoku puzzles, 1-per-page, with a page of hints and a page of answers in the back. These booklets are in PDF ...
1000 Sudoku Puzzles large print with Answers included 100 ...
www.walmart.com
sudoku puzzle book for women: 1000 Sudoku Puzzles large print with Answers included 100 Very Easy Sudoku, 100 Easy Sudoku, 100 Medium Sudoku, 200 Hard ...
Pin on puzzles - Pinterest
www.pinterest.com
Evil Sudoku Online #1939560 - Live Sudoku. Evil Sudoku puzzle number 1939560. You should master the game in order to solve this very hard Sudoku. Go over all ...
Sudoku Hard | Etsy
www.etsy.com
Check out our sudoku hard selection for the very best in unique or custom, ... Sudoku Puzzles with Solutions | 200 Sudoku Puzzles from Easy to Hard ...
Sudoku Printable from easy to the most difficult
1sudoku.com
Sudoku printable. Print free sudoku puzzles, from 4 to 6 per page and according to 5 levels: easy, medium, difficult, expert and evil. Print the solutions ...
Free hard printable Sudokus! - PrintMySudoku
www.printmysudoku.com
Download and print millions of free sudokus (from easy to very hard). ... A new hard sudoku every minute ! ... include solutions add small numbers and rules ...
Sudoku Assistant -- Solving Techniques - St. Olaf College
www.stolaf.edu
Grid Analysis examples. Other advanced techniques are required to solve more difficult Sudoku puzzles such as this one. These techniques are based on one of the ...
Difficult Sudoku With Answers
ck.goodwebshop.site
Difficult sudoku with answers. Free hard sudoku printable puzzles. Print free hard sudoku puzzles, in PDF or can print 4 or 6 puzzles per page and print the ...
Latest Very Difficult Sudoku Puzzles - Updated list - 7Sudoku
www.7sudoku.com
All the puzzles in this page are rated very difficult. Very Difficult Sudoku Puzzles very difficult. sudoku puzzle published on 2021/11/22 sudoku puzzle ...
Sudoku Puzzles: Hard - MathSphere
www.mathsphere.co.uk
The aim of a Sudoku puzzle is to fill in the grid so that each row, each column and each box contains all the numbers from 1 to 9. Usually the grid is 9 by 9,.
Hard sudoku puzzles online - solve difficult web sudoku for free
sudoku.com
Play hard level Sudoku online on Sudoku.com. Our daily difficult web sudoku puzzles are suitable for people, who possess an excellent knowledge of sudoku ...
Sudoku - Hard
www.dadsworksheets.com
These hard sudoku puzzles have fewer clues than the others on the site and ... Each puzzle page is part of a printable PDF with an answer key to help when ...
Hard Level - 27 Givens - Step-by-Step Solution - Web Sudoku
www.websudoku.com
Every Sudoku puzzle we provide comes with its step-by-step solution, such as the hard example shown below. The step-by-step shows one way to solve puzzle using ...
Extreme Sudoku - Hard and Difficult Printable Sudoku Puzzles ...
www.extremesudoku.info
Difficulty depends on the type of steps required to solve them, and also on the number of each type of step. See our guide to solution rules for hard sudoku ...
Sudoku Hard Strategy and Techniques level 4 game 1
suresolv.com
Hard fourth level Sudoku puzzle 1, Strategies Techniques and Solution. Submitted by Atanu Chaudhuri on Thu, 16/04/2020 - 01:07. Sudoku hard Strategy and ...
Sudoku Solving Techniques - Kristanix Games
www.kristanix.com
Solving a hard Sudoku puzzle will require quite a different set of techniques compared to an easy one. This article presents nine such techniques; ...
100 Free Printable Sudoku Puzzles - Memory Improvement Tips
www.memory-improvement-tips.com
There is a link to the Solutions on the puzzle page as well. The printable sudoku puzzles pages below are listed in order of difficulty.
Example Puzzles and Solutions
sandiway.arizona.edu
Difficult · Vegard Hanssen puzzle 2155141 · Challenge 2 from Sudoku Solver by Logic ...
Hard Sudoku Puzzles
www.sudoku.ws
Hard Sudoku Puzzles. Play an interactive sudoku, or try one of our printable hard sudokus. Hard Sudoku Puzzle 1 · Hard Sudoku Puzzle 2
Sudoku - The New York Times
www.nytimes.com
Default Difficulty. This is the difficulty that will be automatically selected when you first visit Sudoku. Easy Medium Hard ...
How To Use Sudoku XY-Wing To Solve Difficult Sudoku
www.sudokuessentials.com
Your ability to identify and solve this pattern will often break the logjam and lead you to the solution of a challenging Sudoku game.
What is the toughest sudoku in world? - Quora
www.quora.com
Originally Answered: What is the hardest sudoku puzzle ever created? And what makes it so difficult? According to Finnish mathematician Arto Inkala, ...
Sudoku techniques - Conceptis Puzzles
www.conceptispuzzles.com
The scanning technique is also very useful for hard puzzles up to the point where no further progress can be made and more advanced solving techniques are ...
Printable Sudoku Logic Puzzles
www.puzzlesandbrains.com
Printable Sudoku logic puzzles for kids and adults with answers in 6 by 6 and 9 ny ... We offer puzzles in 2 formats: 6 by 6 and 9 by 9, and in 4 difficulty ...
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION
www.amazon.com
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION: VERY LARGE PRINT (65pt font) - One Puzzle per page [CRAFTERS, SUDOKU] on Amazon.com.
Sudoku Solutions - Solver And Helper | Play Thousands Of ...
www.sudoku-solutions.com
The solver provides several analysis features which allow you to check if a puzzle is valid, rate the difficulty of a puzzle or get hints on how to solve a ...
Free daily Sudoku games from the Los Angeles Times
www.latimes.com
Check back each day for a new puzzle or explore ones we recently published. Back to all games→. Choose a difficulty level:.
The Miracle Sudoku May Be the Hardest Puzzle Ever
www.popularmechanics.com
The Miracle Sudoku adds challenging chess-themed restrictions to an almost empty grid. · Even easy sudoku grids require deductive reasoning, but ...
Guide to solving a hard, challenging Sudoku puzzle
www.sudokudragon.com
Using advanced strategies to solve a challenging puzzle solution step-by-step. a, b, c, d, e, f, g, h, i. A ...
How to Solve Sudoku Puzzles of Any Difficulty - The Habitat
thehabitat.com
This allows them to visit other boxes while remembering what their answers could be. It also enables many of the more complex Sudoku ...
Sudoku Difficulty
www.sudokuoftheday.com
How do we rank the difficulty of Sudoku puzzles? ... The higher the total cost, adding up over the whole solution, the harder the puzzle!
Extremely Hard Sudoku Puzzles for Experts
sudoku9x9.com
Play extremely hard Sudoku puzzles in our expert area. Be prepared to spend time on these crazily tough puzzles.
Advanced Sudoku Solving Techniques and Tips
sudokusolver.com
So, as we increase the difficulty Super Fiendish, the time has come to present the essential techniques for solving the most difficult Sudoku puzzles.
Hard Sudoku puzzles
images.template.net
Hard Sudoku by www.sudokupuzzle.org. Answers. Sudoku #1. 6. 2. 8. 5. 3. 4. 1 ... Hard Sudoku by www.sudokupuzzle.org. Answers. Sudoku #5. 8. 7. 6. 4. 3. 1.
FREE Printable Sudoku Puzzles
www.puzzles.ca
Sudoku puzzles to print and solve. Two per page. Three levels of difficulty: easy, medium, hard.
Hard Sudoku Puzzles for Kids - Free Printable Worksheets
www.kidsmathgamesonline.com
Check out our hard sudoku worksheets for kids and enjoy a range of free printable puzzles. Challenge students with some difficult sudoku puzzles that are ...
9x9 Sudoku Puzzles
www.sudoku-download.net
The Sudokus are offered in different difficulty levels and they have all different solutions. So if you solved the easy puzzles, you can download the medium or ...
Tough Sudoku Puzzles by Krazydad, Volume 1
krazydad.com
Each of my books contains a collection of eight sudoku puzzles, 1-per-page, with a page of hints and a page of answers in the back. These booklets are in PDF ...
1000 Sudoku Puzzles large print with Answers included 100 ...
www.walmart.com
sudoku puzzle book for women: 1000 Sudoku Puzzles large print with Answers included 100 Very Easy Sudoku, 100 Easy Sudoku, 100 Medium Sudoku, 200 Hard ...
Pin on puzzles - Pinterest
www.pinterest.com
Evil Sudoku Online #1939560 - Live Sudoku. Evil Sudoku puzzle number 1939560. You should master the game in order to solve this very hard Sudoku. Go over all ...
Sudoku Hard | Etsy
www.etsy.com
Check out our sudoku hard selection for the very best in unique or custom, ... Sudoku Puzzles with Solutions | 200 Sudoku Puzzles from Easy to Hard ...
Sudoku Printable from easy to the most difficult
1sudoku.com
Sudoku printable. Print free sudoku puzzles, from 4 to 6 per page and according to 5 levels: easy, medium, difficult, expert and evil. Print the solutions ...
Free hard printable Sudokus! - PrintMySudoku
www.printmysudoku.com
Download and print millions of free sudokus (from easy to very hard). ... A new hard sudoku every minute ! ... include solutions add small numbers and rules ...
Sudoku Assistant -- Solving Techniques - St. Olaf College
www.stolaf.edu
Grid Analysis examples. Other advanced techniques are required to solve more difficult Sudoku puzzles such as this one. These techniques are based on one of the ...
Difficult Sudoku With Answers
ck.goodwebshop.site
Difficult sudoku with answers. Free hard sudoku printable puzzles. Print free hard sudoku puzzles, in PDF or can print 4 or 6 puzzles per page and print the ...
Sudoku Puzzles: Hard - MathSphere
www.mathsphere.co.uk
The aim of a Sudoku puzzle is to fill in the grid so that each row, each column and each box contains all the numbers from 1 to 9. Usually the grid is 9 by 9,.
Hard sudoku puzzles online - solve difficult web sudoku for free
sudoku.com
Play hard level Sudoku online on Sudoku.com. Our daily difficult web sudoku puzzles are suitable for people, who possess an excellent knowledge of sudoku ...
Latest Very Difficult Sudoku Puzzles - Updated list - 7Sudoku
www.7sudoku.com
All the puzzles in this page are rated very difficult. Very Difficult Sudoku Puzzles very difficult. sudoku puzzle published on 2021/11/22 sudoku puzzle ...
Hard Level - 27 Givens - Step-by-Step Solution - Web Sudoku
www.websudoku.com
Every Sudoku we create has a unique solution which can be reached by logic alone. The difficulty of a puzzle is determined by the depth of logic required.
Extreme Sudoku - Hard and Difficult Printable Sudoku Puzzles ...
www.extremesudoku.info
Difficulty depends on the type of steps required to solve them, and also on the number of each type of step. See our guide to solution rules for hard sudoku ...
Sudoku - Hard
www.dadsworksheets.com
These hard sudoku puzzles have fewer clues than the others on the site and ... Each puzzle page is part of a printable PDF with an answer key to help when ...
100 Free Printable Sudoku Puzzles - Memory Improvement Tips
www.memory-improvement-tips.com
There is a link to the Solutions on the puzzle page as well. The printable sudoku puzzles pages below are listed in order of difficulty. If you are new to ...
Sudoku Hard Strategy and Techniques level 4 game 1
suresolv.com
Hard fourth level Sudoku puzzle 1, Strategies Techniques and Solution. Submitted by Atanu Chaudhuri on Thu, 16/04/2020 - 01:07. Sudoku hard Strategy and ...
Printable Sudoku Logic Puzzles
www.puzzlesandbrains.com
Printable Sudoku logic puzzles for kids and adults with answers in 6 by 6 and 9 ny ... We offer puzzles in 2 formats: 6 by 6 and 9 by 9, and in 4 difficulty ...
FREE Printable Sudoku Puzzles
www.puzzles.ca
Sudoku puzzles to print and solve. Two per page. ... The puzzles are divided into three levels of difficulty. ... 967 & 968 (Puzzle, Solution)
Hard Sudoku Puzzles
www.sudoku.ws
Hard Sudoku Puzzles. Play an interactive sudoku, or try one of our printable hard sudokus. Hard Sudoku Puzzle 1 · Hard Sudoku Puzzle ...
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION
www.amazon.com
SUDOKU Hard - Extreme 200 PUZZLES WITH SOLUTION: VERY LARGE PRINT (65pt font) - One Puzzle per page [CRAFTERS, SUDOKU] on Amazon.com.
Sudoku Solving Techniques - Kristanix Games
www.kristanix.com
Tips on Solving Sudoku Puzzles - Sudoku Solving Techniques ... Solving a hard Sudoku puzzle will require quite a different set of techniques compared to an ...
Example Puzzles and Solutions
sandiway.arizona.edu
Difficult · Vegard Hanssen puzzle 2155141 · Challenge 2 from Sudoku Solver by Logic ...
The 10 Hardest Logic Puzzles Ever Created
www.conceptispuzzles.com
Sudoku is easily the most played and most analyzed puzzle in the world, so coming up with the hardest one is no mean feat. In 2012, Finnish ...
What are the points to keep in mind to solve difficult Sudoku ...
www.quora.com
Originally Answered: Are all sudoku puzzles solvable by logical deductions or some do require a guess at some stage? All Sudoku puzzles are solvable only ...
***A SUDOKU PUZZLE*200 Challenging Puzzles with ...
www.barnesandnoble.com
***A SUDOKU PUZZLE*200 Challenging Puzzles with*Answers Book45 ... If you want to get better at solving sudoku puzzles these tips and tricks ...
Sudoku - Wikipedia
en.wikipedia.org
The previous puzzle, showing its solution. …and its solution. Sudoku (数独, sūdoku, digit-single) (/suːˈdoʊkuː, -ˈdɒk-, sə-/, originally called Number ... of easy and difficult puzzles, The Times introduced both, side by side, ...
Hard Sudoku puzzles
images.template.net
Visit www.suduko.us for more printable sudoku puzzles. Page 3. Hard Sudoku by www.sudokupuzzle. ... Hard Sudoku by www.sudokupuzzle.org. Answers. Sudoku #1.
Most Difficult Sudoku Math and Logic Puzzles Increase Your ...
www.walmart.com
The Largest Sudoku Book In The World - 3000 PUZZLES : Medium - Hard - Extreme - 3 Difficulty Levels - 9x9 Puzzle Grids With Answers At The Back (Paperback).
How To Use Sudoku XY-Wing To Solve Difficult Sudoku
www.sudokuessentials.com
Sudoku XY-Wing can solve some of your most difficult Sudoku puzzles. ... often break the logjam and lead you to the solution of a challenging Sudoku game.
The Miracle Sudoku May Be the Hardest Puzzle Ever
www.popularmechanics.com
The Miracle Sudoku adds challenging chess-themed restrictions to an almost empty grid. · Even easy sudoku grids require deductive reasoning, but ...
300 SUDOKU hard to extreme difficulty with answers Brain ...
www.pinterest.com
Oct 14, 2020 - Free 2-day shipping on qualified orders over $35. Buy Expert Sudoku Puzzle Books: SUDOKU Expert : 300 SUDOKU hard to extreme difficulty with ...
9x9 Sudoku Puzzles
www.sudoku-download.net
All Sudokus that you can download from these pages have principally only one solution. For the easy to difficult puzzles, it is also ensured that always at ...
Mathematics of Sudoku Leads To "Richter Scale" of Puzzle ...
www.technologyreview.com
In addition, each grid can have only one solution. Sudoku puzzles are generally classified as easy, medium or hard with puzzles having more ...
Sudoku Difficulty
www.sudokuoftheday.com
How do we rank the difficulty of Sudoku puzzles? ... The higher the total cost, adding up over the whole solution, the harder the puzzle!
Free daily Sudoku games from the Los Angeles Times
www.latimes.com
Check back each day for a new puzzle or explore ones we recently published. Back to all games→. Choose a difficulty level:.
Hard Sudoku | Etsy
www.etsy.com
Fun Sudoku Kids Worksheets with Answers/ Hard Sudoku Puzzles with Answers/ printable sudoku sheets/ Printable Sudoku 10 page A4/ NinaLaZina. Ninalazina.
How to Solve Hard Sudoku Puzzles - wikiHow
www.wikihow.com
These singles are easy to identify, so spend a few minutes scanning each row, column, and cell for any squares with only one possible solution.
Daily Challenging Sudoku Puzzle
www.sudokudragon.com
For fast, unlimited generation and solution of Sudoku puzzles download and install Sudoku Dragon. It is the complete Sudoku package, including hints, guides, ...
Discovery could lead to more difficult Sudoku puzzles - Phys.org
phys.org
"I think it will help develop multi-dimensional Sudoku puzzles, and answer questions about how to give the initial [clues] in order to ...
Extremely Hard Sudoku Puzzles for Experts
sudoku9x9.com
Expert Area: More Extremely Difficult Sudoku Puzzles. Print. Your Free Sudoku Puzzle: (L6: #925315997).
Hard Sudoku Puzzles for Kids - Free Printable Worksheets
www.kidsmathgamesonline.com
Challenge students with some difficult sudoku puzzles that are sure to test their problem solving skills and ability with numbers. Click on one of the 6 ...
Sudoku Printables by Krazydad
krazydad.com
Hundreds of free Sudoku puzzles for printing. ... of printable Sudoku contains eight puzzles, instructions, hints and answers. ... Challenging Volume 1.
How to Solve Sudoku Puzzles of Any Difficulty - The Habitat
thehabitat.com
To solve a Sudoku puzzle, the player must make sure that each row, ... This allows them to more easily remember their possible answers and ...
brain games sudoku large print - Genie Genius Puzzle Expert
www.adlibris.com
Kjøp boken Genie Genius V: 1 hardest sudoku puzzle expert: 300 Very Difficult Sudoku Puzzles with answers- brain games sudoku large print av Genie Genius ...
Sudoku Assistant -- Solving Techniques - St. Olaf College
www.stolaf.edu
Grid Analysis examples. Other advanced techniques are required to solve more difficult Sudoku puzzles such as this one. These techniques are based on one of the ...
Sudoku Solutions - Solver And Helper | Play Thousands Of ...
www.sudoku-solutions.com
Solves any valid sudoku puzzle. ... Offers thousands of free graded puzzles. ... rate the difficulty of a puzzle or get hints on how to solve a puzzle step ...