Weekly Sudoku Challenge
Eight new puzzles open each week, one per size and difficulty. Only records set during the period count.
How the weekly challenge works
Eight new challenge sudoku open every Monday at 00:00 UTC: one kid-friendly 4×4 starter, two 6×6 puzzles (starter and easy), and 9×9 in five tiers from starter to expert. Each slot has its own puzzle and its own leaderboard.
Challenge puzzles are derived deterministically from the week number, so the same week opens the same puzzle for everyone worldwide. Every puzzle has exactly one solution, which makes the race purely about solving speed.
Only global records set within the week count, and the board freezes when the week ends. Each record shows the finish time together with how many hints were used and whether error checking was on, so unassisted solves stand out.
No account is needed. Enter a nickname after finishing and your record joins the board; local records stay on your device. You can also browse past weeks and replay old challenge puzzles for practice.
Weekly challenge FAQ
When do new challenges open?
Every Monday at 00:00 UTC, all eight slots switch to new puzzles at once. Depending on your time zone that may be Sunday evening or Monday morning — the dates shown use UTC.
Do I have to solve all eight?
No. Every slot has a separate board, so pick whichever fits you. The 4×4 and 6×6 slots make a great first sudoku challenge for kids, while 9×9 expert is a proper weekly workout.
Does using hints void my record?
No. Your record still counts — the number of hints and whether error checking was used are simply shown next to it, so hint-free solves get the recognition they deserve.
What if a puzzle is too hard for me?
The sudoku technique guide walks the difficulty ladder step by step, from naked singles to pairs and triples. Starting from the lower slots and working your way up is a fine strategy too.