Both handle PDFs. Only one keeps your files on your device — and reads them for you.
Smallpdf is a solid tool with a polished UI and broad integrations. But it uploads every file to its servers, charges $9/mo for AI features that remain generic (summarize, chat), and has no document-specific analysis.
ModernPDF processes PDF operations locally via WebAssembly — your files are not uploaded to any server. AI features send only extracted text to Anthropic's API via AES-256 bank-grade encryption — never the file itself. It costs $9/mo (or $49/yr) and includes document analysis for contracts, leases, NDAs, and more.
| Feature | ModernPDF | Smallpdf |
|---|---|---|
| File Privacy | PDF tools process locally; AI sends text via AES-256 encryption Winner | All files uploaded to Smallpdf servers |
| Architecture | WebAssembly — processes locally Winner | Server-side processing |
| AI Document Analysis | 10 document types with structured red-flag reports Winner | Generic AI chat and summarization |
| AI Translation | ✓ Powered by Claude (50+ languages) Winner | ✓ Basic AI translation |
| AI Redaction | ✓ Auto-detect PII Winner | ✓ AI-assisted redaction |
| PDF Tools | 28 tools | 30+ tools More tools |
| Free Tier | 3 tasks/day, 10MB files | 2 tasks/day, 5MB files |
| Account Required | No Winner | Optional (required for some features) |
| Install Required | No — browser only | No — browser, desktop app, mobile app |
| Desktop App | ✗ Web only | ✓ Windows & Mac Winner |
| E-Signatures | ✓ Fill & Sign | ✓ Fill & Sign + request signatures Winner |
| Cloud Integrations | ✗ None (local-first architecture) | ✓ Google Drive, Dropbox, OneDrive Winner |
| Pro Price | $9/mo or $49/yr Cheaper annually | $9/mo (billed annually) |
This isn't a feature difference — it's an architectural one. Smallpdf uploads every file to its servers for processing. They encrypt files with TLS and delete them within an hour, and they hold ISO 27001 certification. That's genuine effort toward security.
ModernPDF's PDF tools (merge, compress, convert, rotate, etc.) process entirely in your browser via WebAssembly — no file is uploaded to any server. For lawyers, healthcare workers, accountants, and anyone handling confidential files, this eliminates a significant risk vector.
For AI features (translation, document analysis, redaction), only extracted text is sent to Anthropic's commercial API via AES-256 bank-grade encryption — the file itself is never uploaded. Anthropic's commercial terms prohibit data retention and model training on inputs. No text is stored after processing. This is a meaningful distinction from Smallpdf, which uploads the entire file for all operations.
Smallpdf added AI features in 2024-2025: summarization, chat with PDF, translation, and a question generator. These are powered by generic LLM capabilities — you upload a document, ask questions, get answers. It's useful for general queries across any document type.
ModernPDF takes a different approach. Instead of generic chat, it offers structured document analysis purpose-built for specific document types. Upload a non-compete agreement and get a formatted breakdown of duration, geographic scope, exceptions, enforceability concerns, and red flags — not a generic summary. The same precision applies to employment contracts, NDAs, lease agreements, closing disclosures, medical bills, insurance policies, and freelance contracts.
Think of it this way: Smallpdf's AI is a general assistant that can read any document. ModernPDF's AI is a specialist that knows exactly what to look for in each document type.
Smallpdf has a slight edge in total tool count (30+ vs 28) and offers more advanced editing capabilities including rich text editing and a desktop application. If you need deep PDF editing — font changes, paragraph reflow, image replacement — Smallpdf's editor is more capable.
ModernPDF covers all the essential operations: merge, split, compress, rotate, crop, convert (JPG, PNG, HEIC, Word), OCR, fill & sign, watermark, redact, page numbers, protect, unlock, flatten, grayscale, and delete/reorder pages. For the vast majority of PDF tasks, both tools get the job done.
Where ModernPDF wins on tooling is speed. Because everything processes locally, there's no upload/download cycle. A 50MB merge completes in seconds, not minutes.
Both tools charge $9/mo at face value. The difference is annual pricing:
That's a $59 difference per year on annual plans. ModernPDF's annual plan works out to $4.08/mo — less than half of Smallpdf's equivalent.
Smallpdf also offers Team plans ($7/mo/seat) and Business plans (custom pricing). ModernPDF currently serves individual users only.
Yes. Free users get 3 tasks per day with a 10MB file limit. No account required. Pro ($9/mo or $49/yr) removes limits and unlocks AI features.
Yes. Smallpdf offers AI summarization, chat with PDF, translation, and a question generator. These are general-purpose tools that work across any document type. ModernPDF offers structured analysis for specific document types with red-flag detection.
Smallpdf is ISO 27001 certified and GDPR compliant. Files are encrypted with TLS and deleted within an hour. It's a professionally secured service. ModernPDF's PDF tools process locally — no file upload required. AI features send only extracted text via AES-256 encrypted connection, not the file itself.
Yes. ModernPDF's AI Document Analyzer supports non-compete agreements, employment contracts, NDAs, lease agreements, closing disclosures, medical bills, insurance policies, and freelance contracts. Each gets a structured breakdown with red flags and key terms — not a generic summary.
ModernPDF's local-first architecture means lower infrastructure costs — PDF operations don't touch our servers. That savings is passed to users. $49/yr vs Smallpdf's $108/yr.
Free to start. Files never leave your device. No account required.
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