Privacy by architecture
Private file tools that do not upload your files
Shrink.run sends the tool to your browser instead of sending your file to a processing server. Here is what that changes — and what it does not.
Local browser tools vs upload converters
| Question | Shrink.run | Upload-based converter | Desktop app |
|---|---|---|---|
| Where is it processed? | Inside the browser tab | On the provider’s server | In the installed app |
| Does the file cross the network? | No | Yes | Usually not; check the app |
| Account required? | No | Depends on the provider | Depends on the app |
| Practical file limit | Your device and browser memory | Plan and server limits | Your device and the app |
| Best fit | Quick private jobs | Cloud workflows and shared storage | Large or advanced jobs |
What “no upload” actually promises
The website still downloads HTML, JavaScript and WebAssembly engines. Google AdSense may also make advertising requests, depending on your consent choice. None of that requires the bytes of the image or PDF you selected. The promise is not “the network is silent”; it is “your file is not sent through it for processing.”
You can check this yourself with the browser network panel. Our verification guide explains what to look for, while the privacy policy documents local storage and third-party code.
When local processing matters most
- Signing or reorganising contracts and application forms.
- Compressing invoices, statements or internal slide decks.
- Converting family photos, ID scans or medical paperwork.
- Using a shared network where an unnecessary upload adds risk.
Start with Sign PDF, Compress PDF, Merge PDF or Compress images.
Frequently asked questions
Do my files get uploaded to shrink.run?
No. The selected file is read by code running in your browser. Shrink.run does not receive a copy of the document or image for processing.
Does no upload mean there is no network activity?
No. The page, converter engines and advertising code still use ordinary network requests. The privacy boundary is specific and testable: those requests do not contain the file you selected.
Are files stored anywhere on my device?
Files normally stay in browser memory while a tool is open. A file handed from the home page to a selected tool is placed briefly in browser storage and claimed once by that tool. The OCR language model is also cached locally so it does not need to download every time.
Is a browser tool always better than a desktop app?
No. Desktop software can be a better choice for very large files, offline work before the page has loaded, or advanced editing. Shrink.run is for quick jobs where installing software or uploading a sensitive file is unnecessary.