--- title: "Free Calcudoku generator with answers | Once Books" description: "A free Calcudoku generator that makes a printable puzzle and its answer in one click. Every puzzle has one solution, with no sign-up and no watermark." source: "https://www.oncebooks.com/tools/calcudoku-generator" --- 1. [Home](https://www.oncebooks.com/) 2. [Tools](https://www.oncebooks.com/tools) 3. Calcudoku generator Free tool # Free Calcudoku generator, with the answer Pick a size and generate a Calcudoku, then print it with its answer. Every puzzle has one solution, with no sign-up and no watermark. It runs on the same engine as our KDP Publisher Studio. PuzzleDesign Difficulty Larger grids and bigger cages are harder. Every puzzle has one solution. 5×5 grid. Fill 1 to N once per row and column so every cage reaches its target. Theme ClassicBoldSoftShadedNavyIndigoSkyTealEmeraldForestPlumBerryCrimsonEmberAmberCocoa **Customise colours** Numbers Cell lines Box lines Page background Style StandardClean Clean drops the title band and footer, leaving the grid. Generate puzzlePrint / save PDF Two pages: the puzzle and its answer. Every puzzle has one solution, checked by the same engine as our KDP studio. ## Want the whole book? This makes one puzzle. Sign up to turn it into a full Calcudoku book for Amazon KDP: hundreds of graded puzzles at any trim, as print-ready PDFs. [Build the full book](https://app.oncebooks.com/publisher-studio/calcudoku/edit?from=calcudoku&v=2&s=eyJkaWZmaWN1bHR5IjoiTUVESVVNIiwiY29sb3JUaGVtZSI6eyJ0aGVtZUlkIjoiY2xhc3NpYyIsIm92ZXJyaWRlcyI6e319fQ) Free to build · pay once to export Preview The puzzle and its answer, as they print. Hide the preview - Calcudoku Medium 1 Puzzle - Calcudoku Medium · Solution 2 Solution Generate puzzlePrint / save PDF ## How to make a Calcudoku puzzle 1. Pick a difficulty. Choose a grid size. Larger grids give the logic more room, so they take longer to solve. 2. Generate the puzzle. Press Generate puzzle. You get a fresh grid, proved to have exactly one solution. 3. Print the two pages. Press Print / save PDF. You get two pages: the puzzle on page one and its answer on page two. ## How to solve a calcudoku Fill the grid with 1 to N once in each row and column so every outlined cage combines by its operator to its target. ### The method 1. Read each cage. The small label is the target and the operator the cage must reach: a sum, difference, product or quotient of its cells. 2. Start with single-cell cages. A cage of one cell is just that number given, so place it first and let it constrain its row and column. 3. List the combinations. For a cage, work out which sets of digits reach its target, then cross off any that repeat a digit in a shared row or column. 4. Cross cages with rows and columns. A digit must satisfy its cage and keep its row and column to 1 to N once each. Where only one option does both, lock it in. **The one rule** 1 to N once per row and column, and every cage hits its target. **What the answer page shows** The completed grid is printed at the back. **How the grades differ** Bigger grids and larger cages leave more combinations to weigh. **Good for** Solvers who like arithmetic with their logic. ## Publishing a whole book? This tool makes one puzzle for home or the classroom. To make a Calcudoku book you can sell on Amazon KDP, Publisher Studio generates hundreds of graded puzzles across a difficulty curve, at any KDP trim, as a print-ready interior and solutions PDF. [See the KDP Calcudoku maker](https://www.oncebooks.com/kdp-calcudoku-maker) ## Questions **What is Calcudoku?** Calcudoku (also called Mathdoku) is a Latin square with arithmetic cages: fill 1 to N once per row and column, and make every outlined cage reach its printed target by its operator. **Is this Calcudoku generator free?** Yes. Pick a difficulty, generate a puzzle and print it with its answer, with no sign-up and no watermark. It is free for classroom, home and personal use. **Does every puzzle have one solution?** Yes. Every puzzle is generated and checked by the same solver our Publisher Studio uses, so the clues fix exactly one solution. A puzzle is never ambiguous or unsolvable. **Does it include the answer?** Yes. Every puzzle prints as two pages: the puzzle on page one and its answer on page two, so you can check your work. **What size are the pages?** The free tool prints at 8.25 by 11 inches, a popular large-print size. Our Publisher Studio will export the same book at any KDP trim, from 5.06 by 7.81 up to 8.27 by 11.69, as a print-ready 300 DPI interior. Short of ideas? Browse our [ready-made printables for this puzzle](https://www.oncebooks.com/calcudoku) and print one today.