📖 How to Use SudokuStreak
SudokuStreak is a feature-rich Sudoku platform that lets you play multiple puzzle variants, track your progress, compete on leaderboards, and improve your solving skills. This guide walks you through everything you need to know.
🎮 Starting a Game
When you open the Play page, you will see an empty board with a Start Game button in the centre. The game does not start automatically — you choose when to begin.
- Select your preferred puzzle type (Classic, Killer, X-Sudoku, or Samurai) using the type buttons at the top of the page.
- Choose a difficulty level from the dropdown: Easy, Medium, Hard, Expert, or Evil.
- Click ▶ New Game to generate a fresh puzzle, or click ▶ Start Game on the overlay to begin.
On mobile, tap the ⚙️ button to reveal the type and difficulty selectors. The New Game button is always visible on the right.
🧩 The Game Board
The Sudoku grid occupies the centre of the screen. Below the grid you will find the number pad and action buttons. At the top of the board is the stats bar showing your current time, error count, and your live Sparks (points) total. On wider landscape screens the controls sit to the right of the board; on phones they stack neatly below it.
Selecting a Cell
Click or tap any empty cell to select it. The selected cell is highlighted with a blue outline. All cells in the same row, column, and 3×3 box are highlighted in light blue so you can see where each number already exists. All cells containing the same digit as your selection are also highlighted.
Entering a Number
With a cell selected, enter a number by:
- Clicking a button on the on-screen number pad (1–9)
- Pressing a number key on your keyboard
If you enter a number that conflicts with the puzzle's solution, the cell turns red and your error count increases. Errors are permanent — they count towards your final score.
Erasing a Number
Select the cell you want to clear and:
- Click the ✕ Erase button
- Press Delete or Backspace on your keyboard
🕹️ Controls & Buttons
| Button | What it does |
|---|---|
| ⏸ Pause | Pauses the timer and blurs the grid so nobody sees your progress. Click ▶ to resume. |
| 💡 Hint | Reveals the correct value for one empty cell. Each hint increases your hint count and reduces your score. You have a limited number of hints per game depending on difficulty. |
| ✕ Erase | Clears the selected cell. |
| ✏️ Notes | Toggles pencil mode. In pencil mode, numbers are written as small candidate notes instead of final values. Notes in a cell are cleared automatically once you place a final digit there. |
| 🃏 Jokers | One-use power-ups (Reveal Row, Freeze Timer, Solve Box). They appear in the top-right of the game screen — see the Jokers section below. |
There is no Undo button — placing a digit is committed immediately, so think before you enter. You can still erase a non-given cell at any time.
Keyboard Shortcuts
| Key | Action |
|---|---|
| 1 – 9 | Enter the number into the selected cell |
| Delete / Backspace | Erase the selected cell |
| Arrow keys | Move selection to an adjacent cell |
| P | Toggle pencil / notes mode |
💾 Game Progress & Refresh
SudokuStreak automatically saves your progress to your browser's local storage as you play. If you close the tab or refresh the page, you will see a "Continue your game" overlay showing how much time has elapsed. Click Resume to continue exactly where you left off.
If you want to start fresh instead, click ▶ New Game and confirm the abandon dialog. Note that abandoning a game counts as a loss and is recorded in your statistics.
📅 Daily Challenge
Every day a new puzzle is generated for all players, in three difficulties (Easy, Medium, Hard). Go to Daily Challenge in the navigation to play today's puzzles. Your time is compared against all other players and displayed on the daily leaderboard.
Below today's puzzles is a calendar archive. Browse to previous months and replay any day you missed — each day shows, per difficulty, whether you have already played it and your best time. This lets you fill in your history and chase the monthly achievements.
Completing the daily challenge extends your streak counter. Keep playing every day to build your longest streak!
🏆 Leaderboard
The leaderboard shows the fastest times for daily challenges. Switch between Daily, Weekly, Monthly, and All Time views. You can also filter by your locale to compete against players in your region.
The leaderboard ranks registered players. You can still play and earn Sparks without an account — pick a name and avatar and start solving — and when you create an account your Sparks total carries over, so you can claim your place on the leaderboard under your own name.
🎖️ Achievements
Achievements are unlocked automatically as you play. They are awarded for milestones such as completing your first game, maintaining a streak, finishing a puzzle without hints, or reaching the top of the leaderboard. Each achievement is shown as a coloured badge medallion — its tier (bronze, silver, gold, platinum, diamond) reflects how hard it was to earn. Check your achievements on your Profile page, where you can also share any badge.
Some examples of achievements you can earn:
- First Step — Complete your first game
- No Help Needed — Finish a game without using any hints
- Perfect Game — Finish with zero hints and zero errors
- Week Warrior — Maintain a 7-day daily challenge streak
- Speed Solver — Complete an Easy puzzle in under 3 minutes
- Evil Slayer — Complete an Evil difficulty puzzle
Monthly daily badges: play every day of a calendar month on a given difficulty to earn that month's badge — finish all three difficulties for a full-month bonus. The calendar archive on the Daily Challenge page makes it easy to mop up any days you missed.
💰 Coins & Shop
You earn coins by completing games. The faster you finish and the harder the puzzle, the more coins you receive. Coins can be spent in the Shop to buy hint packs and special power-ups called Jokers.
🃏 Jokers
Jokers are one-use power-ups that give you a boost during a game. Three types are available:
- Reveal Row — Fills in all correct values in the row of your selected cell.
- Freeze Timer — Stops the timer for 60 seconds, giving you extra time without penalty.
- Solve Box — Automatically fills the correct 3×3 box containing your selected cell.
Jokers are purchased in the Shop with coins or real money. Use them wisely — each is consumed immediately when activated.
👤 Profile & Statistics
Your Profile page shows detailed statistics: total games played, completed, best times per difficulty, average time, and your current and longest streaks. All achievements you have unlocked are displayed with their badges.
You can also change your display name on the profile page (subject to a 30-day cooldown between changes).