Killer Sudoku Combinations

Killer sudoku combinations are the sets of digits that can fill a cage of a given size and add up to its target - also called cage combinations, cage sums, or simply the killer cheat sheet. Every cage in Killer Sudoku shows a target sum, and the first question is always the same: which digits can add up to that? This page is the complete answer: every combination for every cage size from 2 to 9 cells, all 502 of them, with the sums that have only one answer in bold. Keep it open while you play.

What is Killer Sudoku?

Killer Sudoku is Classic Sudoku with one extra layer. The usual rules still hold - each row, column and 3×3 box contains 1 to 9 exactly once - but the grid is also divided into dotted-outline cages, each printed with a small target number. The digits in a cage must add up to that target, and a digit never repeats inside a cage. That last rule is what makes the tables below finite and useful: a cage is a set of distinct digits, so a 3-cell cage summing to 24 can only ever be 7+8+9.

Killer grids usually start with no given digits at all. The cages are the clues.

How to use the tables

Find your cage's size (how many cells it covers), then its target sum. The row lists every set of digits that can fill it. Combinations are written compactly - 137 means the digits 1, 3 and 7 in some order.

If only one combination is listed, you have the cage's exact digits outright, and those are the rows worth memorising. If several are listed, you have still narrowed things enormously, and the rest of the grid will pick the winner: cross out any combination containing a digit that is already used in the cage's row, column or box.

Full combination tables

Cages of 2 to 9 cells. A 1-cell cage needs no table - its sum is its digit.

2-cell cages

Sums 3 to 17 · 36 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
312
413
514   23
615   24
716   25   34
817   26   35
918   27   36   45
1019   28   37   46
1129   38   47   56
1239   48   57
1349   58   67
1459   68
1569   78
1679
1789

3-cell cages

Sums 6 to 24 · 84 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
6123
7124
8125   134
9126   135   234
10127   136   145   235
11128   137   146   236   245
12129   138   147   156   237   246   345
13139   148   157   238   247   256   346
14149   158   167   239   248   257   347   356
15159   168   249   258   267   348   357   456
16169   178   259   268   349   358   367   457
17179   269   278   359   368   458   467
18189   279   369   378   459   468   567
19289   379   469   478   568
20389   479   569   578
21489   579   678
22589   679
23689
24789

4-cell cages

Sums 10 to 30 · 126 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
101234
111235
121236   1245
131237   1246   1345
141238   1247   1256   1346   2345
151239   1248   1257   1347   1356   2346
161249   1258   1267   1348   1357   1456   2347   2356
171259   1268   1349   1358   1367   1457   2348   2357   2456
181269   1278   1359   1368   1458   1467   2349   2358   2367   2457   3456
191279   1369   1378   1459   1468   1567   2359   2368   2458   2467   3457
201289   1379   1469   1478   1568   2369   2378   2459   2468   2567   3458   3467
211389   1479   1569   1578   2379   2469   2478   2568   3459   3468   3567
221489   1579   1678   2389   2479   2569   2578   3469   3478   3568   4567
231589   1679   2489   2579   2678   3479   3569   3578   4568
241689   2589   2679   3489   3579   3678   4569   4578
251789   2689   3589   3679   4579   4678
262789   3689   4589   4679   5678
273789   4689   5679
284789   5689
295789
306789

5-cell cages

Sums 15 to 35 · 126 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
1512345
1612346
1712347   12356
1812348   12357   12456
1912349   12358   12367   12457   13456
2012359   12368   12458   12467   13457   23456
2112369   12378   12459   12468   12567   13458   13467   23457
2212379   12469   12478   12568   13459   13468   13567   23458   23467
2312389   12479   12569   12578   13469   13478   13568   14567   23459   23468   23567
2412489   12579   12678   13479   13569   13578   14568   23469   23478   23568   24567
2512589   12679   13489   13579   13678   14569   14578   23479   23569   23578   24568   34567
2612689   13589   13679   14579   14678   23489   23579   23678   24569   24578   34568
2712789   13689   14589   14679   15678   23589   23679   24579   24678   34569   34578
2813789   14689   15679   23689   24589   24679   25678   34579   34678
2914789   15689   23789   24689   25679   34589   34679   35678
3015789   24789   25689   34689   35679   45678
3116789   25789   34789   35689   45679
3226789   35789   45689
3336789   45789
3446789
3556789

6-cell cages

Sums 21 to 39 · 84 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
21123456
22123457
23123458   123467
24123459   123468   123567
25123469   123478   123568   124567
26123479   123569   123578   124568   134567
27123489   123579   123678   124569   124578   134568   234567
28123589   123679   124579   124678   134569   134578   234568
29123689   124589   124679   125678   134579   134678   234569   234578
30123789   124689   125679   134589   134679   135678   234579   234678
31124789   125689   134689   135679   145678   234589   234679   235678
32125789   134789   135689   145679   234689   235679   245678
33126789   135789   145689   234789   235689   245679   345678
34136789   145789   235789   245689   345679
35146789   236789   245789   345689
36156789   246789   345789
37256789   346789
38356789
39456789

7-cell cages

Sums 28 to 42 · 36 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
281234567
291234568
301234569   1234578
311234579   1234678
321234589   1234679   1235678
331234689   1235679   1245678
341234789   1235689   1245679   1345678
351235789   1245689   1345679   2345678
361236789   1245789   1345689   2345679
371246789   1345789   2345689
381256789   1346789   2345789
391356789   2346789
401456789   2356789
412456789
423456789

8-cell cages

Sums 36 to 44 · 9 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
3612345678
3712345679
3812345689
3912345789
4012346789
4112356789
4212456789
4313456789
4423456789

9-cell cages

Sums 45 to 45 · 1 combinations in total. Bold rows are the sums with only one possible combination.

SumPossible digits
45123456789

The cheat sheet: sums with one and only one combination

These sums have exactly one combination, so a cage of that size and sum tells you its digits with certainty - no deduction needed. They are the highest-value rows on this page:

CellsSum → digits
23 → 12  ·  4 → 13  ·  16 → 79  ·  17 → 89
36 → 123  ·  7 → 124  ·  23 → 689  ·  24 → 789
410 → 1234  ·  11 → 1235  ·  29 → 5789  ·  30 → 6789
515 → 12345  ·  16 → 12346  ·  34 → 46789  ·  35 → 56789
621 → 123456  ·  22 → 123457  ·  38 → 356789  ·  39 → 456789
728 → 1234567  ·  29 → 1234568  ·  41 → 2456789  ·  42 → 3456789
836 → 12345678  ·  37 → 12345679  ·  38 → 12345689  ·  39 → 12345789  ·  40 → 12346789  ·  41 → 12356789  ·  42 → 12456789  ·  43 → 13456789  ·  44 → 23456789
945 → 123456789

The pattern is worth noticing: the unique combinations are always the lowest and highest sums a cage can take, because there is only one way to be that small or that large. Eight-cell cages are unique at every sum - the cage holds all but one digit, and the missing digit is fixed by the total (all nine digits sum to 45, so an 8-cell cage summing to 40 is missing the 5).

Putting them to work

Combinations rarely finish a cage on their own - they hand you a short list, and the grid narrows it. A two-cell cage summing to 16 is 79 for certain. A three-cell 8 is either 125 or 134, and if a 4 already sits in that row, it must be 125.

Two habits make the tables pay off fastest. First, scan a new grid for the unique cages above and pencil them in immediately - they are free information. Second, watch for cages trapped inside a single row, column or box: those digits are then excluded from the rest of that unit, which often cracks a neighbouring cage straight away.

Pair this reference with the rule of 45 and innies and outies, and most Killer grids open up. When a cage spans two boxes, cage splitting and cage-unit overlap take over.

Ready to use them? Play Killer Sudoku and keep this page open in a second tab.


Which Sudoku types is this best for?

The same logic applies across variants, but it pays off more in some than others.


Where to practise this

This technique starts paying off at Easy, which is where puzzles first stop yielding to anything simpler. Reading about a pattern and spotting it on a live grid are different skills - the second one only comes from playing.

Play Easy Sudoku About Easy Sudoku


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