How to Play Number Chain
- 1
Choose Difficulty
Easy chains 3 cells with numbers 1–5. Medium chains 4 cells with 1–7. Hard chains 5 cells with 1–9. Pick your challenge and hit Start.
- 2
Start Your Chain
Click any number in the grid to begin. It becomes the first link in your chain and highlighted cells show which adjacent cells you can pick next.
- 3
Extend — But Don't Overshoot
Click adjacent cells to keep adding to your chain. Watch the running sum bar. If adding a cell would exceed the target, that cell is not accepted and the chain resets.
- 4
Hit the Target Exactly
When your chain sum equals the target exactly, the level is cleared! Your score gets 10 base points plus a time bonus for how fast you solved it.
Key Features
4×4 Number Grid
A grid of numbers is generated fresh each level. Click any cell to start, then extend your chain one adjacent cell at a time — horizontally or vertically.
Exact-Match Target
Your chain's running sum must equal exactly the target number. Going over resets your chain immediately, so plan carefully before each click.
10 Progressive Levels
Each of the 10 levels generates a new grid and target. Score points for speed — the more time remaining when you solve a level, the bigger the time bonus.
Undo & Reset Controls
Click the last cell in your chain to undo one step, or reset the whole chain with a single button. There's no penalty for undoing — only for going over target.
What is Number Chain?
Number Chain is a spatial math puzzle where you trace a path through a grid of numbers, accumulating their sum as you go — like a math version of the classic word ladder game. Each cell you add to your chain must be adjacent (up, down, left, or right) to the previous one, and the total must hit the target exactly without going over. It blends arithmetic with spatial reasoning: you need to plan your path in advance, consider which numbers are reachable from your current position, and avoid dead ends that would force you over the target. Every level is freshly generated, so no two games are ever identical.
Why Play Number Chain?
- 1
Combines Math with Spatial Thinking
Unlike pure arithmetic drills, Number Chain requires you to plan a path — building both addition fluency and spatial reasoning at the same time.
- 2
Every Puzzle is Unique
Levels are randomly generated with a guaranteed solution, so you can play infinitely without seeing the same grid twice.
- 3
Strategic Depth at Any Age
Easy mode is great for young learners practicing addition to 15. Hard mode forces adults to think several steps ahead with totals reaching 45+.
- 4
Speed Bonus Rewards Efficiency
You earn extra points for solving levels quickly, so even expert players have a reason to keep optimizing their path-finding.
Frequently Asked Questions
How is the target sum determined?
Each level generates a random grid, then finds a valid path of the required length and uses its sum as the target. This guarantees there is always at least one solution.
Can I visit the same cell twice in a chain?
No — each cell can only appear once per chain. This is what makes path-planning challenging: you can't loop back to a cell you've already used.
What happens if I can't reach the target?
You can always reset your chain and start from a different cell. Since the grid is guaranteed to have at least one valid path, a solution always exists — it may just require a different starting point.
How is the score calculated?
Each level awards 10 base points plus the number of seconds remaining on the timer. Solving a 60-second level in 10 seconds earns 10 + 50 = 60 points.
What happens when I run out of time?
The timer runs out and you lose one life. The same level reloads with a fresh timer so you can try again. Lose all 3 lives and the game ends.
Is there a difference between difficulty modes?
Yes: Easy uses numbers 1–5 and requires a 3-cell chain (small totals, easy planning). Medium uses 1–7 with 4 cells. Hard uses 1–9 with a 5-cell chain, producing larger targets and requiring more complex path planning.