Learning Kakuro: A Short, Opinionated Reading List
Kakuro rewards technique far more than arithmetic. Almost everything you need is contained in one idea — a run of n cells summing to s has only so many possible digit sets, and where two runs cross, only the digits both allow can survive. The resources below teach that idea from several directions.
Every link was opened and checked in August 2026. There is at most one link per website, so nothing here is padding, and each entry says what it is actually for. Where a page has an author worth knowing, they are named.
Start here: the rules, stated properly
| Resource | Why this one |
|---|---|
| Kakuro — Nikoli | The originator's own page, in English. Nikoli introduced the puzzle to Japan in 1980 and named it; their statement of the rules is the reference text, and they note their own puzzles keep the arithmetic deliberately minimal |
| Kakuro rules and info — Grandmaster Puzzles | The clearest one-paragraph statement of the rules anywhere, with an annotated example puzzle constructed by Thomas Snyder (world puzzle champion). Also gives the Cross Sums history in two lines |
Technique: how solving actually proceeds
| Resource | Why this one |
|---|---|
| Kakuro techniques — Conceptis | An 11-step worked solve that walks a real grid from empty to finished. Progresses from combination analysis and constraint elimination through magic blocks to arithmetic reconciliation — deducing a cell from the difference between a row sum and a column sum. Conceptis supplies Kakuro to 100+ countries, so this is the house method of the largest producer |
| Tips and tricks: solve Kakuro without sweat — Sourendu Gupta | The best free technical treatment. Names five techniques — divide and conquer (isolating a block joined to the rest by a single "linking square"), unique partitions, unique intersections, intersections without partitions, and elimination by evidence — with worked diagrams and complete partition lists to length 4. Written by a physicist at TIFR |
| Beginner and intermediate strategies — ATK Solutions | Five practical strategies with screenshots: common numbers, pencil marks, pairs/triples/quadruples, combo elimination, and testing pencil marks to a contradiction. Dated in presentation — the comments run 2009–2017 — but the substance holds |
| How to Solve Kakuro — wikiHow | The illustrated step-by-step walkthrough, useful if the tabular explanations above move too fast. Cited in the reference thread below |
The combination tables
Every strong solver leans on these. They are the multiplication table of Kakuro.
| Resource | Why this one |
|---|---|
| Kakuro combinations — Kakuro Conquest | The complete set: every valid digit set for runs of 2 cells (sums 3–17) through 9 cells (sum 45), with the unique combinations marked. Use it as a filter — list the sets for one clue, then delete every set that the crossing clue forbids |
| Cage combinations — BrainBashers | Presented for Killer Sudoku, but a cage and a run are the same object — n distinct digits summing to s — so the table transfers directly. Unique combinations are shown in green. Note that BrainBashers no longer publishes Kakuro itself |
Practice grids
| Resource | Why this one |
|---|---|
| Krazydad Kakuro | Free printable PDF "books" of eight puzzles, graded by size and difficulty. The best source if you solve on paper |
| Menneske Kakuro | A very large archive running to 30×30. Worth knowing the standing criticism: a reviewer in the reference thread below rated it poorly because the puzzles under-deliver on their stated difficulty and the grids do not print cleanly |
Theory, and something to cite
| Resource | Why this one |
|---|---|
| Kakuro — Wikipedia | The standard overview, and the usual entry point to the mathematics of unique partitions and the puzzle's complexity |
| "The Computational Complexity of the Kakuro Puzzle, Revisited" — Springer | Fun with Algorithms (5th International Conference). The citable source for the fact that Kakuro is NP-complete — there is no known polynomial-time method that solves every instance |
| CSP-Rules / KakuRules — Denis Berthier (GitHub) | A published constraint-solver whose Kakuro module implements the resolution rules from Berthier's Pattern-Based Constraint Satisfaction and Logic Puzzles (2nd ed., 2015, ISBN 978-1-326-35064-2), where chapter 15 (pp. 401–444) is given over to Kakuro. Read this if you want to know how a program solves what you solve by eye |
| Math Circle worksheet — University of Washington | Kakuro used as teaching material with school-age students. A good model if you ever have to explain the puzzle to a room |
Worth reading once: the community's own reference list
| Resource | Why this one |
|---|---|
| Kakuro references — The New Sudoku Players' Forum | A thread started in 2013 by Denis Berthier to build a classified Kakuro bibliography — books, published articles, websites and software, each split by whether it covers resolution rules, generation, or puzzles. What makes it worth the visit is the second voice: Bill Smythe reviews the linked sites bluntly and rates them, including telling Berthier to drop one from his own list. Some links have rotted since 2013; the judgement has not |
Selection note: candidates were drawn from web search and each page was opened and verified before being listed. Sources with only passing mentions were left out, as were content-farm pages rehashing the same beginner advice. A dedicated Kakuro subreddit does not meaningfully exist — the nearest large communities are the general puzzle and sudoku subreddits.