Puzzle Island Layout
Numbered islands
Key Benefit: The number shows how many lines must attach to that island. Draw straight paths sideways or up and down.
Bridges (Hashi) Generator
Build Bridges (Hashi) books solvers love
Connect numbered islands with single or double lines. Every number must match its bridge count, and all islands have to link into one single network. Clean, simple puzzle design.
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2,400+ publishers · 18,000+ books
Bridges (Hashi) Generator Engine
KDP ready
✓ Print ready
4 sizes
Grid sizes
Connected
All islands
< 2 min
Per book
Unique
One solution per puzzle
Workflow Application
Who uses Librava bridges creator?
Logic puzzle book designers and math teachers generate island-connecting bridge grids.
Japanese Logic Books
Publishers compile hashi (bridges) puzzles to cater to fans of advanced Japanese logic puzzles on KDP.
Spatial Reasoning Lessons
STEM teachers print bridge connection sheets to help students learn network pathing and logic.
Mindful Brain-Training
Creative designers print relaxing island-connecting grids for daily mindfulness puzzle packs.
âš¡ Generation Guide
Generate Bridges in three steps
Pick your options and download your book. No complicated setups required.
Workflow Breakdown
3 Steps
Fully verified, print-compliant pipeline.
- Step 01
Pick size and difficulty
Choose grids from 6×6 to 12×12. Decide how many islands you want on the page.
- Step 02
System builds the puzzle
The system places islands and checks that there is only one correct way to solve the grid.
- Step 03
Download the PDF file
Get a print-ready file containing your puzzles, the solution section, and the rules sheet.
✨ Features
Custom Hashi Puzzles & Answers
Make clean island puzzles. Every PDF has original pages, numbered answer pages, and standard KDP borders.
Solved Bridge Solution
Full network connection
Key Benefit: The answer matches every island count exactly. Every circle links back to the main group.
Easy to Hard Difficulty Levels
Change the difficulty
Key Benefit: Use small grids for beginners and larger networks for advanced solvers. Each setup has one clear answer.
Print Ready KDP Book
Formatted for Amazon KDP
Key Benefit: Clean interior files for standard KDP dimensions. Comes with pages for puzzles, answers, and instructions.
Comparative Matrix
Bridges Generator vs. Other Design Options
Look at how different tools handle island connections, grid setup, and answers.
| Capability Check | Bridges Generator | Free Puzzle Sites | Hired Designers |
|---|---|---|---|
| Solvability | Checked by system (all pieces connect) | Broken island numbers or broken paths | Drawings done by hand in vector programs |
| Grid options | 4 distinct options | One size only | Templates drawn to order |
| Answers | Small solution grids at the back | Links to separate files | Extra files to place by hand |
| Production time | Under 2 minutes for 100 puzzles | Hours spent gathering pages | 5 to 7 days for vector files |
| Cost | Free / Premium Credits | Monthly membership fees | $150 to $300 for a single project |
Specs & Safety
Architectural & Print Safety Guidelines
Librava's output files undergo deterministic geometry calculations based on your total page count to calculate the exact gutter margin, outer trim, and bleeding path safeguards required by retail publishing presses.
This completely eliminates alignment rejections and scaling distortion during physical bindings, making it the perfect platform for self-publishers looking to scale.
- Output Format
- Print-Ready PDF
- Resolution
- 300 DPI Vector Lines
- Grid Sizes
- 6×6, 8×8, 10×10, 12×12
- Difficulties
- Easy, Medium, Hard, Expert
- Logic Verification
- Single solvable path per puzzle
- Backmatter Options
- Solved bridge layouts
Reviews
What KDP authors say
"I published 8 books last month. Each one took under 20 minutes start to finish. Librava is insane."
Maria T.
KDP publisher · 42 books
"The output quality genuinely surprised me. I used to do everything manually — now I just review and tweak maybe 5%."
James R.
Puzzle book author
"Made $1,200 in my first month selling themed books for seniors. This tool basically pays for itself in a week."
Linda K.
Retired teacher, side hustle
Frequently Asked Questions
Answers & Specifications
2-day free trial · Cancel anytime
Your first book, ready in minutes
Join 2,400+ publishers already using Librava to build passive income on Amazon KDP. You keep 100% of your royalties — always.