How to play Number Groups
The rules
- The grid is split into groups of 1 to 5 cells, shown with thick borders.
- A group of N cells holds each number from 1 to N exactly once.
- Two cells that touch, also diagonally, never hold the same number, also across group borders.
Every puzzle has exactly one solution, and you reach it by logic, without guessing.
How to play here
- Select a cell: click it or use the arrows.
- Number: keys 1–5 or the number pad. A number larger than the cell’s group is not available.
- Notes: press N or the Notes button, or hold Shift with a number.
- Erase: Delete or 0.
- Equal numbers that touch, or a number twice in a group, are marked with diagonal stripes. An empty cell where no number fits gets an ×.
Difficulty levels
| Level | Size | What it takes |
|---|---|---|
| Easy | 5×5 | Single option and only place |
| Medium | 6×6 | + Neighbours |
| Hard | 7×7 | + Neighbours, eight times or more |
| Expert | 7×7 | + Try it |
Techniques
Single option
When a cell’s group and its touching cells leave just one number, that’s the number.
Only place
When a number the group still needs fits in only one of its cells, it goes there.
Neighbours
A number must go in one of a few cells of its group. If another cell touches all of them, that cell can’t hold the number.
Try it
A cell has two possible numbers. Put one of them in and follow the easy steps. If you reach a dead end, the other number is right.
Tips
- Start with groups of 1 and 2 cells: a 1-cell group is always 1.
- Look for the 5s: only a group of 5 cells can hold one.
- Take notes for the cells of big groups.
FAQ
- Can equal numbers touch across a group border?
- No. Two cells that touch, side by side or diagonally, never hold the same number, whatever group they are in.
- Is there a new puzzle every day?
- Yes. A new Number Groups puzzle is published every day at each of the four levels: easy, medium, hard and expert. Earlier puzzles are in the archive.
- Do I need an account to play?
- No. You play right in your browser, with no sign-up and no cookies. Your progress is saved in your browser.