Killer Sudoku (BrainBashers)
Four dated killer sudokus a day: sudoku rules plus cages that must add up.
Every day: Four new killer sudokus every day (Easy, Easy/Medium, Medium and Medium/Hard), dated and the same for every visitor, with a few weeks of past days to pick from. New puzzle: Midnight GMT (the site lets you set your own time zone).
BrainBashers posts four killer sudokus a day, from Easy to Medium/Hard. The grid has no given digits; instead coloured cages carry a sum, and you place 1 to 9 in every row, column and block so each cage adds up to its clue without repeating a digit.
About Killer Sudoku (BrainBashers)
Killer Sudoku on BrainBashers keeps the classic sudoku rules (every row, column and 3x3 block holds 1 to 9) and adds cages. Each cage is outlined with a dotted line and shaded in a colour, and the small number in its corner is the total its digits must reach. A digit may not repeat inside a cage. The page points out that this differs from CalcuDoku, the site's other cage puzzle, where numbers can repeat in a cage and other operations are used.
Every day brings four puzzles graded Easy, Easy/Medium, Medium and Medium/Hard. Each opens on its own dated page made by Kevin Stone, with check, pencil marks, undo, answer, print and restart buttons, options to show mistakes or duplicates, and an on-screen clock if you want one. A help page explains the method, and a separate page lists the possible digit combinations for each cage total and size, which is the main tool for this kind of puzzle.
The puzzles change at midnight GMT, or at the time zone you set, and a date list keeps the last few weeks available. The site has no adverts and needs no account.
It suits sudoku players who like a bit of arithmetic and want a set of graded grids each day.
How to play Killer Sudoku (BrainBashers)
- Open the Daily Killer Sudoku page and choose one of today's four levels.
- Read the cage totals: the digits inside each outlined cage must add up to the small number in its corner.
- Place 1 to 9 so every row, column and 3x3 block has each digit once, with no repeats inside a cage.
- Use pencil marks for candidates and press check to test your entries.
- Reveal the answer if you need it; four new puzzles arrive after midnight GMT.
Tips
- Learn the fixed cages: two squares adding to 3 must be 1 and 2, and two adding to 17 must be 8 and 9.
- Every row, column and block adds up to 45, so subtract the cages inside a block to find a lone square.
- Keep the site's combinations page open for larger cages until the common ones are familiar.
- Start with the Easy grid; the Medium/Hard one leans on the 45 rule across several blocks.
Questions
How many killer sudokus does BrainBashers post each day?
Four: Easy, Easy/Medium, Medium and Medium/Hard.
Can a digit repeat in a cage?
No. In BrainBashers Killer Sudoku a number cannot appear twice in the same cage.
When do the puzzles change?
At midnight GMT, or at the time zone you set on the site.
Is it free?
Yes. There are no adverts and no account; the site runs on voluntary support.
Games like Killer Sudoku (BrainBashers)
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The Times Killer Sudoku
The Times' daily killer sudoku, a long-standing newspaper version
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The Daily KenKen (SudokuWiki)
Another cage-and-arithmetic grid, with all four operations
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