GamesPopularDailyBlogHall of Fame
PlayBrain

Number Slider

Slide numbered tiles into order — fewer moves means more stars!

0:00
Moves0

Use arrow keys or click/tap tiles adjacent to the empty space.

≤ 60 moves
≤ 120 moves
≤ 240 moves

How to Play

  1. Click a tile next to the empty space to slide it into the gap.
  2. Arrange all tiles in numerical order from 1 to 15, left to right, top to bottom.
  3. Timer starts on your first move and stops when solved.
  4. Choose grid size: 3x3 (easy), 4x4 (classic), 5x5 (expert).
  5. Earn stars by solving in fewer moves. Fewer moves = more stars!
  6. Best scores per grid size are saved automatically.

Tips

●Solve row by row — place the top row first, then work down.
●Work in pairs — position the last two tiles of a row together.
●Corner technique — rotate tiles into place using the corner gap.
●Blue-tinted tiles are already in the correct position.
●Use arrow keys for faster play on desktop.
Share:PostRedditShare

You might also like

🧠
Memory Match
Play →
⏱️
Timed Memory Match
Play →
⌨️
Typing Speed
Play →
⚡
Reaction Time
Play →
📖
Related Article
Best Free Number and Math Puzzle Games 2026 | No Download

Frequently Asked Questions about Number Slider

What is the 15 puzzle?
The 15 puzzle (also called the sliding puzzle) is a classic brain teaser with 15 numbered tiles in a 4x4 grid with one empty space. Slide tiles into the empty space to arrange them in numerical order. Invented in the 1870s, it's one of the oldest puzzles in the world.
How do you solve a sliding number puzzle?
Work row by row from top to bottom. First solve the top row, then the second row, and so on. For the last two rows, solve column by column. The key is moving tiles into position without disturbing already-placed tiles.
What grid sizes can I play?
PlayBrain offers 3x3 (8 tiles, beginner), 4x4 (15 tiles, classic), and 5x5 (24 tiles, expert) sliding puzzles. Start with 3x3 to learn the technique, then work your way up.
Is every sliding puzzle solvable?
Not every random arrangement is solvable! Exactly half of all possible tile arrangements can be solved. Our puzzles are always generated from solvable positions by making random legal moves from the solved state.
What's a good time for the 15 puzzle?
Casual players typically solve the 4x4 in 2-5 minutes. Regular players aim for under 1 minute. Speed solvers can finish in under 20 seconds using learned algorithms and pattern recognition.

About Number Slider

Number Slider is the classic 15-puzzle brought to life in your browser, challenging you to arrange numbered tiles in sequential order by sliding them through a single empty space. This deceptively simple puzzle has fascinated mathematicians since the 1870s and remains one of the most studied problems in combinatorial optimization. The game offers three grid sizes: a gentle 3x3 with 8 tiles, the classic 4x4 with 15 tiles, and an expert 5x5 with 24 tiles. The key technique is solving row by row from top to bottom, then handling the final rows column by column. Speed solvers develop algorithms and pattern recognition that let them finish the classic 15-puzzle in under 20 seconds. Your move count and time are tracked so you can measure improvement across sessions.

How to Play

  1. Click a tile adjacent to the empty space to slide it into the gap
  2. Arrange all tiles in numerical order from top-left to bottom-right
  3. Work row by row from the top, locking completed rows in place
  4. Finish with the fewest moves possible to beat your personal best