KAKURO KOKORO
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How to play

Kakuro Kokoro rules

A fresh heart-shaped puzzle every time you visit. Learn the rules once — then it clicks.

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Heart-shaped grid
The white cells form a heart. Fill every white cell with a digit 1–9 to solve the puzzle.
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Hit the sums
Each run of cells must add up to the number shown in the clue triangle at the start of that row or column.
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No repeats
Within a single run, every digit must be unique — you can't use the same number twice in one sum.
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Unique solution
Every puzzle has exactly one valid solution. Logic alone will get you there — no guessing required.
Solving strategies

Think like a solver

These four techniques cover most situations you'll encounter.

Beginner
Forced combinations
Some sums have only one possible set of digits. A 2-cell run summing to 3 must be 1+2 — no other option.
3 in 2 = {1,2}
Beginner
Intersect runs
A cell belongs to both a row run and a column run. If both runs restrict it to the same digit, fill it in.
row ∩ col = one digit
Intermediate
Subset elimination
If two cells in a run must together hold two specific digits, those digits can't appear in other runs that cross them.
{3,7} pair frees up 5
Intermediate
Sum bookkeeping
If you know some cells in a run, subtract them from the total. The remainder narrows the choices for remaining cells.
16 − 9 − 4 = 3 remaining

Digit Combination Calculator

Stuck on a tricky clue? The calculator shows every valid set of digits for any sum + run length.

Open calculator →
Kakuro Kokoro — the book

Take the hearts with you

A curated collection of heart-shaped Kakuro puzzles — graded from gentle warm-up to mind-bending challenge — printed on quality paper for focused, screen-free solving.

  • Heart-shaped grid on every page
  • Puzzles graded Easy → Expert
  • Complete solutions in the back
  • No fluff — pure puzzles
♥  Get it on Amazon
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