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International Sudoku Day

Test your logic skills and celebrate International Sudoku Day - solve puzzles and unlock new levels of fun!

Wednesday

September 2026

Last updated February 7, 2026 · by the Holiday Calendar Team

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YEARLY DATESeptember 9

OBSERVED INInternationally

CATEGORYPop Culture

SUBCATEGORYGaming

INTRO

Introduction

PHOTO

Get ready for a day full of brain-teasing fun on International Sudoku Day on September 9! This holiday was created to honor the iconic Japanese logic puzzle, which has been enjoyed by people all around the world since its introduction in 1979. Whether you're a sudoku master or just starting out, this is your chance to show off your skills and have some good old-fashioned fun.

TIMELINE

International Sudoku Day Timeline

Sudoku Invention

The modern version of Sudoku was invented by Howard Garns, an American architect and puzzle enthusiast.

Sudoku in Japan

The puzzle game was introduced in Japan by Nikoli in the puzzle magazine Monthly Nikolist, where it gained its name and popularity.

Computer-Generated Sudoku

Hong Kong judge Wayne Gould developed a computer program that could generate Sudoku puzzles quickly. This facilitated its spread worldwide.

Sudoku in UK Newspaper

The Times in the UK started publishing Sudoku puzzles daily, significantly increasing its popularity in the western world.

World Sudoku Championship

The inaugural World Sudoku Championship was held in Italy, demonstrating the game's global appeal.

International Sudoku Day Initiated

The World Puzzle Federation established International Sudoku Day to be celebrated on September 9 (9/9) - reflecting the 9x9 grid of a Sudoku puzzle.

GET INVOLVED

How to Celebrate International Sudoku Day

Play Sudoku

The most obvious way to celebrate International Sudoku Day is by playing! There are many versions of Sudoku available online and in app stores.

HOST

Host a Sudoku tournament

Invite friends and family over for a tournament to see who can solve the most puzzles in the shortest amount of time.

CREATE

Create your own puzzles

Design your own puzzles and challenge yourself and others. You can even share them online with other Sudoku fans!

TRY

Try variations of Sudoku

There are lots of different variations of Sudoku, such as Killer Sudoku, Jigsaw Sudoku, and Samurai Sudoku. Try them all out and see which one you like best!

WHY THIS DAY MATTERS

Why We Love International Sudoku Day

It's a lot of fun

Yes, Sudoku can get challenging at times – but that only makes it more enjoyable when you solve the puzzle! It gives you a sense of accomplishment and satisfaction knowing that you put your mind to work and outsmarted it in the end. So get those number pencils ready and enjoy some good old fashioned problem solving!

Sudoku is challenging

Sudoku is a great way to challenge yourself and keep your brain sharp. With its grids of numbers and complicated rules, Sudoku can be just as complex as any crossword puzzle - but you don't need to worry about guessing words or spellings!

It can be played anywhere

You don't need to have a physical board game to play Sudoku - all you need is the rules and a few pieces of paper. This means it's an easy game to travel with, so you can test your skills on the bus or train ride home!

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