KenKen, Calcudoku & Mathdoku: Why This Puzzle Has Different Names

If you've seen this arithmetic grid puzzle called "Calcudoku" on one site, "Mathdoku" on an app, and "KenKen" in your newspaper, you're not looking at three different puzzles — they're all the same game. The reason it has so many names isn't fashion; it's a trademark. "KenKen" is a registered brand, so everyone who wanted to publish the puzzle without a license came up with their own name for it. This article untangles the aliases — KenKen, Calcudoku, Mathdoku, KenDoku, and a few more — so you always know what you're playing, whatever the label says.

Want to just play it under any name? It's right here at KenKen.

They're all the same puzzle

Whatever it's called, the rules are identical: fill a square grid so every row and column contains the digits 1 to N once (the Latin square rule), and so the digits in each outlined cage combine — using ×, ÷, +, or − — to make the cage's target. If a grid has arithmetic cages and the no-repeat-in-a-line rule, it's this puzzle, no matter what name sits at the top. (New to it? The KenKen rules lay it out, and the how-to-play tutorial shows it step by step.)

So why the pile of names? One word: trademark.

KenKen: the trademarked brand

"KenKen" is the registered trademark, and it's the name most people know — it appears in The New York Times and many other major newspapers. The name comes from the Japanese word ken (賢), meaning "cleverness" or "wisdom"; doubling it ("KenKen") roughly conveys "cleverness squared." Because the name is owned, only licensed outlets can legally call the puzzle KenKen, which is precisely what spawned all the alternatives.

Calcudoku: the popular generic name

"Calcudoku" — a blend of calculate and the -doku suffix from sudoku — is the most widely used generic name, especially on independent puzzle sites and in software. If a publisher wants to offer the puzzle without licensing the KenKen brand, Calcudoku is the go-to label. It carries real standalone recognition; plenty of solvers know the puzzle only by this name.

Mathdoku: the math-forward alias

"Mathdoku" is another common generic name, popular on apps and in educational contexts. It puts the arithmetic front and center — "math" plus "-doku" — which makes it self-explanatory for newcomers and a natural fit for classroom use. Functionally it's identical to KenKen and Calcudoku.

KenDoku and other variants

A few more names circulate:

• KenDoku — another sudoku-flavored alias, sometimes used to dodge the trademark while keeping the "ken" nod.
• Mathku / Minukai / Square Wisdom — assorted regional or app-specific labels.
• CalcuDoku (capitalized variants) — same as Calcudoku, just styled differently.

They all describe the same arithmetic Latin-square puzzle.

A quick glossary

Here's every name you're likely to meet, all pointing to the same puzzle:

• KenKen — the trademarked brand; from Japanese ken, "cleverness."
• Calcudoku — the leading generic name; "calculate" + "-doku."
• Mathdoku — math-forward generic name, common in apps and schools.
• KenDoku — sudoku-style alias avoiding the trademark.
• Mathku / Square Wisdom — assorted regional or app names.

Does the name change how you play?

Not at all. The strategy is identical regardless of the label: place single-cell cages, factor the constrained cages, and read each cage as a combination list, then eliminate with the Latin square rule. That approach works whether the site says KenKen, Calcudoku, or Mathdoku. For the full method, see the KenKen strategy guide, and for where the puzzle came from, the history of KenKen.

The takeaway: don't let the names confuse you. They're all doorways into the same clever arithmetic puzzle. Pick whichever your favorite site uses, and start solving.

Frequently asked questions

Is Calcudoku the same as KenKen?

Yes, exactly the same puzzle. "KenKen" is a registered trademark, so independent publishers use the generic name "Calcudoku" (from "calculate" + "-doku") instead. The rules — a Latin square grid with arithmetic cages — are identical.

What is the difference between KenKen, Calcudoku, and Mathdoku?

There's no difference in the puzzle itself — all three are the same arithmetic grid game. "KenKen" is the trademarked brand, while "Calcudoku" and "Mathdoku" are generic names publishers use to offer the puzzle without licensing the KenKen name. Mathdoku emphasizes the math and is common in education.

Why does KenKen have so many names?

Because "KenKen" is a registered trademark. Only licensed outlets can legally use it, so other publishers created their own names — Calcudoku, Mathdoku, KenDoku, and more — to publish the same puzzle. The trademark is the entire reason for the alias fragmentation.

What does the name KenKen mean?

It comes from the Japanese word ken (賢), meaning "cleverness" or "wisdom." Doubling it to "KenKen" conveys something like "cleverness squared," reflecting the puzzle's origin as a brain-training tool created by a Japanese educator.

Which name should I search for?

"KenKen" returns the most results because of its newspaper presence, but "Calcudoku" is the most common name on independent and ad-free puzzle sites, and "Mathdoku" surfaces app and classroom versions. All three lead to the same puzzle.