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PDF Lite vs PDF Max vs PDF Ultra X27
Status, 14 October 2026: Culltron desktop apps are launch candidates. Access is gated and no public installer is published yet. This page describes how the product works today in our release candidates.
If you want to edit a PDF without Adobe and without uploading it anywhere, this is how Culltron's three PDF editions compare. All three run locally.
| Feature | Lite | Max | Ultra X27 |
|---|---|---|---|
| Read, search and annotate | ✓ | ✓ | ✓ |
| Merge, split and reorder | ✓ | ✓ | ✓ |
| Fill simple forms | ✓ | ✓ | ✓ |
| Edit text and images in place | – | ✓ | ✓ |
| Convert to and from Office formats | – | ✓ | ✓ |
| OCR for scanned documents | – | ✓ | ✓ (with batch queues) |
| Sign and redact | – | ✓ | ✓ |
| Aria: extract and summarise | – | – | ✓ |
PDF Lite comes free with Culltron OS and isn't sold separately. See PDF Max.
About PDF Max
PDF Max
A local PDF workstation. Nothing is uploaded unless a separate connected workflow says so explicitly.
- A viewer with page thumbnails, zoom, rotate, jump, keyboard navigation and text search.
- Organise, rotate, delete, crop and extract exact page ranges. Merge files, turn images into a PDF, export pages to PNG and extract text.
- Edit metadata and add watermarks and page numbers.
- Inspect and fill AcroForm fields, author fields after review, and optionally flatten. Add bookmarks and page labels.
- Local preflight checks for structure, accessibility and print, plus bounded OCR to create searchable copies.
- AES-256 password encryption and authorised decryption, available when qpdf is installed. Each change writes a separate copy and a receipt.
Ultra X27: adds stamps, presets for watermarks and page numbers, appearance-only signature marks, metadata cleaning, three lossless optimisation profiles, batch merge/split/watermark/numbering, and document binders.
Limits: Production edits refuse dynamic XFA forms and PDFs that already carry signatures rather than silently invalidating them. Signature marks are visual and are not digital signatures.
Release status: built and tested in the repository. A public download appears only after signing, checksum verification and release approval; see Downloads.