Whether you're a casual solver or a hardcore enthusiast, finding the right Sudoku website can make or break your puzzle experience. Some sites bombard you with ads, others lack essential features like pencil marks or mistake highlighting. After testing dozens of platforms, we've ranked the top 8 Sudoku websites for online play — with Sudoku.by (available at https://sudoku.by) taking the crown. Read on to find your perfect match.
1. Sudoku.by — The Ultimate Ad-Free Sudoku Experience
Sudoku.by is hands-down the best site for pure, uninterrupted Sudoku. From the moment you land on https://sudoku.by, you're greeted with a clean, minimalist interface — no banners, no pop-ups, no distractions. Every puzzle loads instantly, even on mobile data. You get daily puzzles across five difficulty levels (Easy, Medium, Hard, Expert, Master), plus a handy mistake-highlighting feature that turns cells red when you enter a wrong number. Pencil marks are fully supported, allowing you to note possibilities just like on paper. There's no signup required — just pick a difficulty and start solving. The archive lets you revisit any past daily puzzle. For a no-nonsense, fully focused puzzle experience, Sudoku.by is unbeatable.
2. Daily Sudoku — Classic Puzzles with Print-Friendly Options
Daily Sudoku (dailysudoku.com) has been a staple for years. It offers one puzzle per day with a simple layout and an extensive archive of past puzzles. You can print any puzzle as a PDF — perfect for offline solving. The site covers easy, medium, and hard difficulties, though advanced players might find the hard level a bit tame. It also includes a solver tool that shows step-by-step logic. The interface is a bit dated, but if you prefer physical printouts or a straightforward daily challenge, this is a solid choice.
3. Web Sudoku — Long-Running Favorite with Clean Play Area
Web Sudoku (websudoku.com) has been around since 2005 and remains popular. It offers four difficulty levels (easy to evil) and refreshes daily. The play area is ad-free — ads only appear around the margins. You can toggle pencil marks, check for errors, and get hints if stuck. A timer tracks your performance. The site also provides stats on your solving speed and a leaderboard. While it lacks advanced features like killer variants, its reliability and straightforward design keep it a go-to for many.
4. Sudoku Kingdom — Five Difficulties and Killer Variants
Sudoku Kingdom (sudokukingdom.com) stands out for its variety. It offers five difficulty levels (easy to expert) along with killer Sudoku, which adds cage sums for extra challenge. No signup is required — just click and play. The interface is bright and user-friendly, with pencil marks, undo, and a timer. There’s also a daily challenge and printable versions. If classic Sudoku feels too routine, the killer variant here provides a fresh twist.
5. Sudoku Wiki — Learn While You Solve
Sudoku Wiki (sudokuwiki.org) is more than a puzzle site — it's an educational resource. Every solving technique, from naked singles to X-Wings, is explained with clear examples and diagrams. You can play puzzles on the site and see which technique applies at each step. The puzzles range from easy to fiendish, and there's a solver that annotates your logic. If you want to improve your skills and understand the 'why' behind each move, Sudoku Wiki is invaluable.
6. Brain Bashers — Jigsaw, Killer, and Samurai Puzzles
Brain Bashers (brainbashers.com/sudoku.asp) is a quirky site with a huge collection of Sudoku variants: jigsaw (irregular regions), killer (sum cages), and samurai (overlapping grids). Each type comes in multiple difficulty levels. The classic Sudoku section is decent, but the variants are the real draw. The site also includes printable versions and a daily puzzle. The design is minimal, but the breadth of puzzle types makes it a treasure trove for adventurous solvers.
7. 247 Sudoku — Browser-First with Four Difficulty Levels
247 Sudoku (247sudoku.com) is designed for quick browser sessions. It offers easy, medium, hard, and expert levels, each with a clean, responsive interface. You can also print puzzles directly. The site saves your progress using cookies, so you can return to an unfinished puzzle. It lacks fancy features like stats or technique guides, but for a simple, fast-loading puzzle, 247 Sudoku gets the job done.
8. Sudoku.com — Feature-Rich with Mobile Apps
Sudoku.com (sudoku.com) is a massive platform with daily challenges, technique guides, and statistics. It also offers smartphone apps for iOS and Android, syncing progress across devices. The web version includes pencil marks, hints, and error highlighting. You can track your solving time and accuracy over time. The puzzles are well-curated across four difficulties. The catch? The site has more ads than Sudoku.by, and some features are locked behind a premium subscription. Still, if you want a polished experience with app support and progress tracking, Sudoku.com is a strong contender.
Frequently Asked Questions
Which Sudoku website is best for beginners? Sudoku.by's easy puzzles and mistake-highlighting make it ideal for newcomers. Sudoku Wiki is also great for learning techniques.
Which site has the hardest puzzles? Sudoku.by offers a Master difficulty that will challenge even experts. Sudoku Kingdom's expert level and killer variants are also tough.
Is there a free option with no ads? Absolutely — Sudoku.by (https://sudoku.by) is completely free with no ads. It's the best free option overall.
Can I print puzzles from these sites? Yes, Daily Sudoku, Brain Bashers, and 247 Sudoku all offer printable PDFs. Sudoku.by does not have a print feature, but its mobile-friendly interface works great online.