Free daily Sudoku · No signup · No ads
Sudoku, beautifully done.
Start filling in today's board right here — a fresh puzzle every day in four difficulties, plus a solver, kids boards, printable PDFs and a real techniques library.
100% free · no signup · no ads · works on phone & desktop
Play now · medium
Tap a cell, then a number
What's inside
Everything you'd expect from a Sudoku site — done properly.
Daily puzzles
A new Easy, Medium, Hard and Expert board every day. One unique solution each.
Kids boards
Tiny 4×4 grids for ages 5–7 and 6×6 for ages 7–10. Same rules, gentler scale.
Solver & hints
Paste any Sudoku, get a step-by-step walkthrough explaining the technique used.
Learn & print
A real techniques library — Hidden Single, X-Wing, the lot — and free printable PDF packs.
See it in action
12 seconds. One puzzle. No clutter.
Keyboard entry, a hint engine that explains why, and calm visual feedback that keeps a solve flowing. No popups. No ads.
Today's challenge
Four daily puzzles — every difficulty
Fresh every day. Each published board is checked to have exactly one solution.
easy
easy Sudoku
~5 min · 38 clues to start
Play →medium
medium Sudoku
~12 min · 32 clues to start
Play →hard
hard Sudoku
~35 min · 28 clues to start
Play →expert
expert Sudoku
~35 min · 27 clues to start
Play →Built for every player
Free Sudoku for kids, teens, adults and beginners
Zeloku scales with every player. Tiny 4×4 grids for kids ages 5–7, 6×6 for kids 7–10, and the classic 9×9 Sudoku for teens, adults and beginners. All puzzles free to play online.
A 60-second warm-up
Don't read about Sudoku — play one, right here.
A tiny 4×4 puzzle uses the same three rules as the full 9×9: rows, columns, and 2×2 boxes — each must contain 1, 2, 3 and 4 with no repeats. Tap a cell, tap a digit. Most people finish in under a minute.
- · No signup, no ads. Just play.
- · A new mini every day — rotates from a curated pool.
- · Mistakes light up amber so you can fix them as you go.
Mini daily · Jul 30
A 60-second warm-up
Sudoku, by need
Honest, evidence-based answers to the questions players actually ask.
Whether you're looking for an ADHD-friendly focus exercise, an evening wind-down routine, or the variant rules to a Killer board — these long-form guides explain it cleanly, with sources where we have them.
Sudoku for ADHD
Why a 9×9 grid is one of the few things ADHD brains stay with — and the right difficulty to start at.
Read →Sudoku for memory loss
What the PROTECT and ACTIVE studies actually show — and a sensible five-minute daily routine.
Read →Sudoku before bed
When a logic puzzle helps you fall asleep — and when frustration makes it worse.
Read →Killer Sudoku rules
Cages, sums and the 45 rule — with the full cage-sum cheat-sheet.
Read →The hardest Sudoku ever
Arto Inkala's 2012 puzzle, on the board — with the story of why it's so hard.
Read →Learn techniques
Hidden Single, Naked Pair, X-Wing — the real techniques that make Sudoku tractable.
Browse →Tips for absolute beginners
Ten habits that turn a 30-minute Easy puzzle into a 5-minute one. In order of impact.
Read →Solve hard Sudoku step-by-step
A seven-step tutorial for Hard boards — no guessing, ever. The two techniques that unlock every stall.
Read →Sudoku as brain training
Does it actually work? Evidence-based answer from the PROTECT & ACTIVE studies, plus a 5-minute routine.
Read →Sudoku for the classroom
Free lesson plan, printable rules, and PDF packs for K–8 teachers. No prep required.
Read →Learn Sudoku
Free Sudoku techniques, clearly explained.
Stop guessing. Learn the real Sudoku techniques — naked single, hidden single, pointing pair, X-Wing — each with annotated examples, the Sudoku rules they rely on, and free practice puzzles.
Browse the library
Beginner
Hidden Single
A pattern-based way to place a digit with certainty.
Intermediate
Naked Pair
A pattern-based way to place a digit with certainty.
Intermediate
Pointing Pair
A pattern-based way to place a digit with certainty.
Advanced
X-Wing
A pattern-based way to place a digit with certainty.
Printable Sudoku
Free printable Sudoku PDFs
Download and print Sudoku booklets for every level — easy, medium, hard, expert and kids 6×6 — completely free, no signup.
20 easy puzzles
A clean, printable Sudoku PDF booklet — free to download for travel, classroom or weekend play.
6×6 for kids
A clean, printable Sudoku PDF booklet — free to download for travel, classroom or weekend play.
Hard booklet
A clean, printable Sudoku PDF booklet — free to download for travel, classroom or weekend play.
Play free
More ways to play Sudoku online
Your daily five minutes
Play free Sudoku every day.
One Sudoku puzzle a day, online and free, no signup required. Growing smarter, calmer, sharper — five minutes at a time.
Start today's free puzzle