Number Island
Group neighbouring numbers into islands that hit each target total, with a new board every day.
Every day: A dated set of island puzzles each day (Easy, Medium and Long), the same for every player: group adjacent cells so each island adds up to one of the targets; past days are in the archive. New puzzle: Once a day; puzzles are labelled with the date.
Number Island is a free daily addition puzzle. Each board gives you a few target totals and a grid of numbers; you join horizontally or vertically adjacent cells into islands whose sums match the targets, working around blocked squares.
About Number Island
Number Island was made for people who like numbers more than letters: the site notes that the Wordle-style daily trend has mostly served word lovers. Each day brings a dated puzzle at several sizes, labelled Easy, Medium and Long on the site, from a 3x3 board with three targets up to large boards with as many as fifteen.
The board shows numbers and crossed-out squares. You click cells to build an island of cells joined above, below, left or right, and when an island's total matches one of the targets, both turn blue. Crossed squares cannot be used, which sometimes leaves a lone number or a trapped group that is an island on its own. Keep going until every target has its island.
The site suggests it for building addition fluency and number flexibility, for parents and teachers as well as puzzle fans. There is an archive of earlier days and a stats page, and no sign-up is needed.
It suits players who want a calm arithmetic puzzle and anyone helping a child practise mental addition.
How to play Number Island
- Open numberisland.com and choose a difficulty.
- Look at the target totals above the board.
- Click adjacent cells (up, down, left, right) to form an island; it turns blue when its sum matches a target.
- Make one island for every target, then try another size or an older day from the archive.
Tips
- Start with the smallest targets: they have the fewest ways to be made.
- Look for numbers cut off by crosses; they may already be a complete island.
- Try the easy board first; the rules are the same at every size.
Questions
Is there a new puzzle every day?
Yes. Each day's puzzles are dated, and earlier days are in the archive.
Can cells join diagonally?
No. Only cells above, below, left or right are adjacent.
Do I need an account?
No. It is free with no sign-up.
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