Keep confidential documents and personal photos off other people's servers. Compress images, merge PDFs, and convert videos on your own device with WebAssembly and your browser's built-in codecs.
No upload · Processed in your browserDrop a file and we'll suggest the right tools
Image · PDF · Video · Audio
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The six file tasks people reach for most
Image, PDF, video, and audio tools, grouped by file type
Your files stay on your device.
Skip the round trip to a server. Processing starts on your device.
No sign-up, no install. All you need is a browser.
From the moment you choose a file to the moment you save the result, every step happens inside this browser.
The page reads only the files you hand it through the file picker or drag and drop, using the browser's File API. Choosing a file doesn't send it anywhere, and this site never makes a network request that carries file contents, file names, or exact sizes.
Heavy work runs in a Web Worker, separate from the page, so the screen stays responsive. Images go through WebAssembly codecs such as MozJPEG and OxiPNG, PDFs through pdf-lib and qpdf, and video and audio through the browser's built-in codecs (WebCodecs). Only when those codecs can't handle a format is the FFmpeg (WebAssembly) engine downloaded, once.
The result is built as a Blob in browser memory and saved to your device when you press Download. Close the page and the in-memory files are gone. Only when you move to another tool on this site are your input files held briefly in this browser's storage and then deleted — and even then they never leave your device.
Read how in-browser processing works and how to verify it yourself →
Many online converters receive your file on a server and process it there. A server can't work on a file it doesn't have, so the file stays on the operator's server until processing ends and it is deleted. ZEKILO Studio does the opposite: it sends the processing program to your browser, so there is no server that needs to receive your file.
| Compared | Server-based converters | ZEKILO Studio |
|---|---|---|
| Where the file is | Sent to a server and kept there until it's deleted | Stays on your device |
| Where it is processed | The operator's server | This browser (your device's CPU and memory) |
| Time it takes | Sending + processing + downloading | Processing only; depends on your device |
| Deleting the file | Follows the operator's retention policy | Nothing was sent, so nothing to delete on a server |
| Limits | Size and usage caps set by the server | Device memory and browser support |
| How to check | You rely on the operator's word | See it yourself in the DevTools Network tab |
What this site does exchange: page files, processing engines, and advertising and analytics scripts. Analytics may record which tool was used, the file format, and a rough size range — never file contents, file names, or exact sizes.
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