A scratch pad to help you fill in a Sudoku puzzle. You still have to solve it yourself!

Every day, you get three fresh Sudokus. Explained: what is a naked or hidden pair?

- If the Sudoku is still empty, select a Daily Sudoku, or enter or copy/paste one under Import.
- Each number may appear only once in each row, column, or block (3x3 square).
- In each cell, you can fill in the number you found, or multiple numbers to indicate the candidates—these will be shown smaller.
- Use
**Eliminate** to remove candidate numbers if they are found already in the same row, column, or block. This way, you sometimes find new numbers (light blue), if so, repeat the elimination process.
**Click on any figure in the column headings** to highlight their position in the Sudoku, click again to remove the highlighting. If a number is highlighted, Shift-click on a cell to fill in that number, Ctrl-Shift-click to remove that number as a candidate, repeat to undo.
**Colouring tool**; Ctrl-click on a cell to make it green, Ctrl-click again to make it blue, Ctrl-click a third time to remove the colour. All colours are removed when you click on a column heading. Here is an explanation of the *colouring technique*
- At any moment, you can save your position. You will find the saved board below, click on it to restore, or add it to your favorites/bookmarks to return to it later.
- If you're stuck, click on
**Hint** to get a helpful remark. This will indicate which method you can use where. Not all logical methods have been implemented yet, only those that are mentioned below after 'easy' and 'medium'.
**Solve puzzle** tries to find a solution to the current diagram. If you entered a wrong number (shown in red), it will not find a solution. In that case, remove or correct the red number, or go back to the original Sudoku (for example by clicking below 'Daily Sudoku'), and click again on **Solve puzzle**.
- Of course, you can also print the Sudoku and solve it offline: yes, this page is printer-friendly, just try it.

Questions or comments? sudoku@harryonline.net.

Have you ever tried a Str8ts puzzle?

## Daily Sudoku

- 23 May: easy, medium, tough
- 22 May: easy, medium, tough
- 21 May: easy, medium, tough
- 20 May: easy, medium, tough
- 19 May: easy, medium, tough
- 18 May: easy, medium, tough

- easy
- Can be solved using
*single* techniques: there is only one candidate in a cell, or there is only one cell in a row/column/block where a number can be placed;
- medium
- You need more advanced techniques, such as combining the positions in different rows/blocks or columns/blocks, or pairs of numbers that can only be placed in two cells (naked/hidden pairs);
- tough
- Can't be solved with these techniques only.

## Sudoku Links

## Import Sudoku

Below you can paste a Sudoku as text. Use any character for the open cells, except the digits 1-9, spaces, '+', '-', '|', and '>'. The rows in the Sudoku may, but don't have to be on separate lines.