Comparison
File Viewer is a pure frontend file preview component for internal tools, intranet systems, and private deployments. It is designed for quick business-file preview, triage, search, print, export, and self-hosted delivery. It is not a professional editor, and it does not promise native-app fidelity for every complex file.
File Viewer vs conversion services
| Approach |
Strengths |
Limits |
| Backend conversion |
Can normalize files to PDF/images for caching, archival workflows, permission auditing, and unified fallback behavior |
Requires conversion workers, queues, temporary files, fonts, caches, retries, and cleanup; private deployment can be costly |
| Office Online / cloud services |
High fidelity, low maintenance, mature collaboration features |
Not always suitable for intranet, private deployment, sensitive files, offline environments, or strict compliance requirements |
| File Viewer |
Pure frontend, self-hostable, lazy-loaded, and easy to embed in business applications |
Complex Office / CAD files still need real-file regression; not a replacement for professional editors or archival conversion |
When File Viewer fits best
- Files should not be sent to a third-party conversion service.
- The app runs in an intranet, private deployment, offline environment, or strict CSP setup.
- One component needs to cover Office, PDF/OFD, CAD, archives, email, images, media, code, and structured data.
- The product goal is preview, triage, search, print, export, and download rather than editing.
- The frontend team wants renderer/preset composition instead of many unrelated viewer embeds.
When backend conversion is better
- Long-term archival requires every file to become a stable PDF or image.
- Very large files make browser memory or mobile performance the main constraint.
- The workflow needs maximum fidelity, batch conversion, OCR, burned-in watermarks, audit records, or asynchronous review queues.
- The team already runs a reliable LibreOffice, OnlyOffice, or commercial conversion service and can absorb the operational cost.
Recommended mix
Many production systems can combine both approaches:
- Use File Viewer for instant browser-side preview by default.
- Trigger backend PDF conversion for archival, contracts, audit, or strict consistency cases.
- Self-host Worker, WASM, font, and vendor assets with the rest of the app's static resources.
- Collect real compatibility feedback through issues and sanitized samples instead of trusting synthetic files only.
Validation checklist
- Try Word, Excel, PowerPoint, PDF, DWG, ZIP, and EML in the demo.
- Validate the real formats your product cares about with sanitized files.
- Check mobile WebView behavior, intranet static paths, Worker/WASM MIME types, CSP, and fonts.
- For Office / CAD fidelity, review the format fidelity notes.