Sudoku
Calm • Focus-friendlyChoose a difficulty, or take on today’s daily puzzle. Smooth controls, notes, highlights, timer + PB, and local saves.
Choose a difficulty
Pick based on your mood — quick warm-up, steady flow, or a deeper session.
Easy
Gentle pace, great for relaxing.
Medium
RecommendedBalanced and satisfying.
Hard
More constraint, more deduction.
Expert
Fewer givens, longer deduction chains.
Master
Slow, careful, and rewarding.
Play Sudoku Online on Gridcore
Gridcore Sudoku is built for focus: clean visuals, smooth controls, and a calm solving experience. Play instantly in your browser with multiple difficulty levels, a daily puzzle, notes mode, a timer, personal best tracking, and local saves.
How to Play Sudoku
New to Sudoku? Read our beginner guide on how to play Sudoku for a step-by-step explanation and basic strategies.
Sudoku is a 9×9 number puzzle. Your goal is to fill the grid so that each row, each column, and each 3×3 box contains the numbers 1 through 9 exactly once.
- Each row must include 1–9 with no repeats.
- Each column must include 1–9 with no repeats.
- Each 3×3 box must include 1–9 with no repeats.
- Use the given numbers as clues and deduce the rest step by step.
Frequently Asked Questions
Can I play Sudoku for free?
Yes. Gridcore lets you play Sudoku online for free, with no account and no downloads.
Does Gridcore save my progress?
Yes. Your current board, notes and timer are saved locally on your device for each difficulty, so you can close the tab and pick up where you left off.
How many difficulty levels are there?
Five: Easy, Medium, Hard, Expert and Master. Each one starts you with fewer given numbers than the last, so the deduction gets longer rather than trickier.
Go back to Gridcore home, or try today’s Daily Sudoku.