Sudoku Factory
Generate, customise, and export individual sudoku puzzle images — on macOS and iOS.
What it does
Turn a seed and a difficulty setting into a ZIP archive of ready-to-use puzzle images — one file per puzzle, no manual layout.
Any grid size
4×4, 6×6, 9×9, 16×16, or 25×25 — each solved by a backtracking solver that guarantees a single solution.
Fine difficulty control
10 difficulty levels, either fixed (all puzzles at the same clue count) or progressive (start easy, end hard).
Deterministic seeding
Same seed + same settings = identical puzzles, every time. Useful for reproducible editions or staggered releases.
ZIP archive export
Images are packed into a single ZIP file, with a readme PDF for metadata. macOS saves to your chosen folder; iOS shares via the system share sheet.
Three output formats
Export as PNG (raster), SVG (vector), or individual PDF pages. All generated at 300 DPI for print-ready quality.
Duplicate prevention
Optional deduplication checks every puzzle against a local registry, so no two generated sets share an identical grid.
Grid sizes
From quick 4×4 grids to massive 25×25 puzzles.
Larger grids (16×16, 25×25) use letters for values beyond 9. 9×9 grids can enable the diagonal X-Sudoku constraint.
Difficulty levels
Level 1 shows roughly 55% of cells. Level 10 shows roughly 24%. Your choice, per puzzle set.
Output formats
| Format | Best for | Notes |
|---|---|---|
| PNG | Social media, blogs, web | Raster at 300 DPI. Includes label (title, volume, difficulty) and optional solution background |
| SVG | Print, vector editing, scaling | Self-contained vector files, editable in Illustrator / Inkscape |
| Single-puzzle images | print-ready |
Available on macOS and iOS
Native apps built with SwiftUI. Same workflow, same output quality, same seed compatibility.
macOS
macOS 14.0+
- Full settings panel with all options visible at once
- Save ZIP to any folder via NSSavePanel
- Live grid preview while you configure
- Progress tracking for long generation runs
iOS & iPadOS
iOS 17.0+
- Adaptive layout: compact form on iPhone, sidebar on iPad
- iOS share sheet — AirDrop, Messages, Files, or any target
Frequently asked questions
Common questions about what this tool does and doesn’t do.
Does it generate printable PDF books?
Sudoku Factory produces individual puzzle files — one per image — packed in a ZIP.
Can I sell the generated puzzles?
Yes. The puzzles are algorithmically generated from your seed — they are your content. The seed-based generation is deterministic: the same seed and settings always produce the same grid, so you can reference them in separate publications.
Do I need an internet connection?
No. All generation happens on-device. Once installed, the app works offline.
Does the app include solutions in the images?
Optionally. You can choose to include solution images alongside the puzzle images. The solutions highlight the empty cells from the puzzle so you can see which numbers were filled in.
What does “seed” mean?
The seed is a number that initialises the random number generator. Every setting choice (grid size, difficulty, seed) produces a unique but repeatable set of puzzles. If you generate twice with the same seed and settings, you get the exact same grids. This is useful for creating reproducible editions.
Can I label the images?
Yes. Each image can include a title label (puzzle number, difficulty, grid size). You can also adjust whether the label appears above or below the grid.
What image formats are supported?
PNG (raster at 300 DPI), SVG (vector for scaling and editing), and individual PDF images.
Ready to generate?
The app is in pre-release. If you’d like early access or have questions, get in touch.
Contact for early access