Stoku
Fill the 9×9 grid so that each column, row, and 3×3 sub-grid contains all digits from 1 to 9.
About the Game
What is Stoku (Sudoku)?
Stoku, also known as Sudoku, is a timeless logic-based number puzzle. Your goal is simple yet deeply satisfying: fill a 9×9 grid so that every row, column, and 3×3 block contains all digits from 1 to 9. No math is required — only reasoning, patience, and a bit of strategy. That’s why Sudoku has become one of the world’s most beloved brain-training games.
Using the Hint Feature Wisely
If you’re stuck, the hint feature can reveal the correct number for one empty cell, helping you get back on track. It’s a great learning tool, but remember — solving puzzles on your own is where the real mental workout happens. Use hints sparingly to sharpen your logic over time.
Why Play Sudoku on Thinko.fun?
Thinko.fun brings Sudoku to life with fast loading, smooth gameplay, and a clean, mobile-friendly interface. Each puzzle is freshly generated, ensuring endless challenges whether you’re a beginner or an expert. With real-time difficulty levels, intuitive controls, and optional smart hints — you can focus on what matters most: the joy of solving puzzles anytime, anywhere, completely free.
Tips & Strategies for Stoku (Sudoku)
Strategy 1: Cross-hatching
This is a fundamental and highly effective technique. To find the correct position for a specific number, you scan the rows, columns, and 3x3 blocks to identify the only possible empty cell for that number. This method helps quickly narrow down the options for empty squares.
Strategy 2: Single Candidate
Look for cells where only one number can possibly be placed. By checking the numbers already present in the same row, column, and 3x3 block, you can often find a cell that has only one remaining valid number. That number is the solution for that cell.
Strategy 3: Hidden Single
This strategy involves finding a number that can only be placed in one specific cell within a row, column, or 3x3 block, even if that cell could also contain other numbers. By identifying all possible candidates for each empty cell, you can find the "hidden single" where a number has only one home.
FAQ for Stoku (Sudoku)
How long does it take to solve a Sudoku puzzle?
The time to solve a Sudoku puzzle varies greatly depending on its difficulty. An easy puzzle might be solved in a few minutes, while a hard one could take an hour or more.
Do I need math skills to play Sudoku?
No, Sudoku is a pure logic puzzle and requires no mathematical calculations like addition or subtraction. The numbers 1-9 are used simply as symbols to represent a set of nine unique items.
What happens when the board is full?
If all cells are correctly filled according to the rules, you have won the game! If the board is full but there are rule violations (e.g., a duplicate number in a row), the puzzle is considered unsolved.
How do I use the hint feature?
The hint feature, when used, will reveal the correct number for one of the empty cells. It's a useful tool if you get stuck, but using it too often can hinder your ability to improve your puzzle-solving skills.