The one-question test
Ask: does another service need to understand this file to do the job? If the answer is no, local processing is usually the better privacy default.
Local tools are best for simple file work
Compression, conversion, merging, typed signing, watermarking, splitting, trimming, and changing audio speed are good local-tool tasks.
Cloud and AI tools still have a place
Cloud services are useful for collaboration and heavy processing. ChatGPT is useful for reading, summarizing, and rewriting. Adobe and full editors are useful for OCR, redaction, advanced PDF editing, and professional document workflows.
Quick comparison
| Tool | Best when | Skip when | Privacy fit |
|---|---|---|---|
| Just Compress | Quick private file jobs. | AI reading or deep editing. | No upload. Free. PDF outputs include a small app logo watermark. |
| Cloud PDF and media tools | Non-sensitive files, collaboration, heavy server processing, shared workflows. | Sensitive files that only need a simple mechanical file operation. | Often secure, but many require upload, server processing, and deletion policies. |
| ChatGPT / AI | Summarizing, reasoning, rewriting, comparing, extracting meaning from content. | Only making a file smaller, converting it, or adding a simple mark. | Useful when content analysis is needed; unnecessary exposure for simple file tasks. |
| Adobe / full editors | OCR, redaction, forms, certificates, advanced page editing, professional workflows. | One quick compression or conversion where no full editor is needed. | Powerful, but heavier than needed for simple no-upload file work. |
- Simple + private task Compress, convert, sign, or watermark: a local tool like Compress PDF.
- Collaboration or heavy processing A cloud service is worth the upload when the work needs a server.
- Understanding content Summaries or analysis: AI such as ChatGPT, with retention in mind.
FAQ
When should a file stay on my device?
Keep it local when it includes private, financial, medical, legal, client, school, or family information and the task is simple.
When should I use ChatGPT?
Use ChatGPT when you need help understanding, summarizing, comparing, or drafting from the file.
When should I use Adobe or a full editor?
Use a full editor for OCR, redaction, forms, page-level design, certificates, and advanced PDF work.
Why choose Just Compress?
Choose Just Compress when you need a fast, free, no-account, no-upload file operation for PDF, audio, video, or photos.