Overview
Sudoku Printable is a free online tool that generates unlimited sudoku puzzles in PDF format. It offers 19 variants (Standard, Diagonal, Windoku, etc.), four grid sizes (4×4, 6×6, 9×9, 16×16), six paper formats, and multiple difficulty levels. No registration is required, and answer keys can be included. It's ideal for teachers, puzzle enthusiasts, and anyone who enjoys screen-free brain training.
just f*ing send it** (jfsendit) is a peer-to-peer file transfer service that uses WebRTC to stream files directly between browsers. No uploads to a server, no accounts, no storage. Files are end-to-end encrypted, and transfers can resume if the connection drops. It supports multi-GB files and folders. The service is completely free and requires no registration.
Feature Comparison
| Feature | Sudoku Printable | just f***ing send it |
|---|---|---|
| Primary Function | Generate and print sudoku puzzles | Peer-to-peer file transfer |
| User Interface | Web-based generator with live preview and settings | Minimalist drag-and-drop interface |
| Customization | 19 variants, 4 grid sizes, 6 paper formats, difficulty levels, font size | None – just file selection |
| Output | Printable PDF with optional answer keys | Short code for direct transfer |
| Registration Required | No | No |
| Data Storage | No user data stored | No files stored on server; ephemeral signaling only |
| Encryption | Not applicable (printable puzzles) | End-to-end encrypted WebRTC |
| File Size Limit | N/A | Multi-GB files supported |
| Resume on Drop | N/A | Yes |
| Target Audience | Teachers, puzzle enthusiasts, parents, seniors | Anyone needing quick, secure file sharing |
| Variants/Options | Standard, Diagonal, Windoku, Odd/Even, Knight, Jigsaw, etc. | Single transfer mode |
| Accessibility | Large print option, kid-friendly grids | No specific accessibility features mentioned |
Pricing
Sudoku Printable: Completely free. No registration, no payment, no limits. Generate unlimited puzzles.
just f*ing send it:** Completely free. No registration, no payment, no limits. Transfers are free.
Pros and Cons
Sudoku Printable
Pros:
- Extremely customizable – 19 variants, multiple grid sizes, paper formats
- No registration or account needed
- Instant PDF download or direct print
- Includes answer keys for self-checking
- Kid-friendly options (4x4, 6x6) for educational use
Cons:
- 16x16 grid is still in beta (may not have unique solutions)
- Limited to sudoku puzzles only – no other puzzle types
- No mobile app – web-only
just f***ing send it
Pros:
- True peer-to-peer – no server storage, maximum privacy
- Supports large files and folders
- Resumable transfers if connection drops
- No registration, no account, no limits
- End-to-end encryption by default
Cons:
- Requires both sender and receiver to be online simultaneously
- Short-lived codes – must share quickly
- No file scanning or moderation – user assumes all risk
- Minimal interface – no advanced features like password protection or expiration
Verdict
Choose Sudoku Printable if you need a versatile, free puzzle generator for education or leisure. It's perfect for teachers creating classroom materials, parents looking for screen-free activities, or puzzle enthusiasts who want endless variety. The customization options are unmatched for a free tool.
Choose just f*ing send it** if you need a private, encrypted, no-hassle way to transfer large files directly between devices. It's ideal for sharing sensitive documents, large media files, or folders without relying on cloud storage. The peer-to-peer architecture ensures maximum privacy.
Both products excel in their respective niches with zero cost and no registration. Your choice depends entirely on whether you need puzzles or file transfers.