What is Local Processing?
Many online converters are upload services: files are sent to a remote server, processed there, and sent back. Local processing avoids that round trip for supported flows. Selected file contents are handled in browser memory by client-side scripts.
The Browser APIs Behind the Scenes
We leverage modern web standards to provide desktop-class utility performance in a website:
- **HTML5 Canvas API:** We redraw and re-encode images locally to change their formats.
- **File & Blob APIs:** We handle your files as local data streams without triggering a network request.
- **WebAssembly (WASM):** For heavy tasks like AVIF encoding or PDF manipulation, we run high-performance compiled code directly in your browser tab.
Comparison: Local vs. Upload
| Feature | Upload-Based Sites | ConvertUnlimited |
|---|
| Privacy | Higher exposure risk because files are uploaded | File contents are processed locally in your browser |
| Security | Server breach risk | No server-side upload endpoint for supported local flows |
| Wait Time | Upload + Download time | Instant local processing |
| Data Usage | Upload + download | Static page load, then local processing for supported flows |
| Internet | Required for processing | Not required after load |
Technical Advantages
Because supported flows process selected file contents locally in your browser, the speed of ConvertUnlimited is only limited by your computer's CPU and RAM. This is why we can support bulk processing of hundreds of files without a subscription fee—we don't have to pay for massive server bandwidth, and neither do you.
What this page does
Discover the technology behind local-first file processing. Learn how we use Canvas, WASM, and File APIs to process images and PDFs without server uploads.
Privacy behavior
Selected file contents are processed locally in your browser for supported workflows. The public site may load ads and analytics; use the privacy build for privacy-sensitive workflows.
Supported workflow
Use this page to understand the workflow, then open the linked tool page when you are ready to process files.
FAQ
Can ConvertUnlimited see my files?
For supported local-processing flows, ConvertUnlimited does not provide a server-side upload endpoint for selected file contents. The public site may still load ads and analytics.
Which version should I use for sensitive documents?
Use the privacy build for privacy-sensitive workflows. It is designed without ads, analytics, remote fonts, or third-party runtime scripts.
Action
Try the local-first experience. Go to the Metadata Remover.