Sudoku Online vs SharedSudoku

Play Sudoku online against friends in real-time 1v1 duels, take on the Daily Challenge and climb its worldwide ranking, or unwind with hundreds of classic puzzles offline. No ads. DAILY CHALLENGE — ONE PUZZLE, ONE RANKING • A new Sudoku every day, the same one for every player. • The week ramps up: easy on Monday, expert on Saturday and Sunday. • Your score is your time plus a penalty for every mistake. Submit it and see where you rank. • Keep your streak alive, look back at previous days' rankings and set an optional daily reminder. MULTIPLAYER SUDOKU — REAL-TIME 1V1 • Create a private game, share the code with a friend and start playing in seconds. • Both players solve the same Sudoku at the same time; every correct number scores a point. • Wrong numbers cost you a time penalty, so think before you tap. • Watch your rival's progress live and race to fill the grid first. CLASSIC SUDOKU — SINGLE PLAYER • Hundreds of hand-picked puzzles in four difficulties: easy, medium, hard and expert. • Progress and best times are saved on every puzzle, so you can pick up where you left off. • Play offline, anywhere: on the train, in bed, on a break. DESIGNED FOR FOCUS • Dark mode and more than 20 themes, light and dark. Lavender and Night are free; Sudoku Pro, a one-time purchase, unlocks the rest. • No ads interrupting your game. • Pencil notes: long-press a cell to jot down up to three candidate numbers. • Clean, distraction-free board with big, readable numbers. • Relaxing music and sound effects you can mute with one tap. • Available in English, Spanish, Catalan, German and French. HOW TO PLAY 1. Pick Single player and a difficulty, the Daily challenge, or Online multiplayer to start a duel. 2. Tap a cell, then tap a number. Long-press to add notes. 3. Fill the grid — or fill more cells than your opponent — to win. Whether you want a quick logic puzzle, a daily Sudoku habit or a competitive number game with friends, Sudoku Online is the Sudoku app that makes solving social. Download it and challenge someone today.

Shared Sudoku brings the classic number puzzle to life with three ways to play: solo, competitive, and cooperative. SOLO MODE Sharpen your skills with classic Sudoku. Choose from three difficulty levels — easy, medium, or hard — and track your progress with detailed statistics including best times, win streaks, and game history. COMPETITIVE MODE Race head-to-head against another player! Both players receive the same puzzle and compete to solve it first. Connect instantly online — no accounts or internet required. COOPERATIVE MODE Work together on a shared board. See your partner's moves in real time as you collaborate to complete the puzzle. Each player's contributions are color-coded so you can see who placed what. FEATURES • Three difficulty levels with unique puzzle generation • Pencil marks for noting candidates • Undo and redo support • Mistake tracking • Number highlighting — long press any number to highlight all instances on the board • Game statistics: best times, win rates, current and best streaks, game history • Online multiplayer — play with anyone, anywhere • Clean, modern interface with haptic feedback Shared Sudoku is completely free with no ads, no in-app purchases, and no data collection.