ICON to PJPEG Converter
FileFlip converts ICON to PJPEG entirely inside your browser, using ImageMagick compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an ICON file to PJPEG?#
- Drop your ICON file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to PJPEG and the conversion starts on its own. FileFlip downloads 14.1 MB of WebAssembly the first time and nothing after that, then runs ImageMagick on your own machine.
- Save the PJPEG file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting ICON to PJPEG lose quality?#
Yes, once. ICON keeps everything and PJPEG does not, so this is the first time the file meets a lossy encoder. At high quality the difference is hard to see, and it is worth keeping the ICON original, because every later re-save of the PJPEG loses a little more.
Is it safe to convert ICON files online?#
Yes, because nothing is uploaded. FileFlip converts ICON files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What ICON to PJPEG actually does to the file#
Converting ICON to PJPEG runs on ImageMagick, downloads 14.1 MB of WebAssembly the first time and nothing after that, encodes a lossless source with a lossy encoder for the first time, and drops transparency and extra images.
| Engine | ImageMagick |
|---|---|
| Conversion path | One step: ICON → PJPEG |
| Downloaded to your browser | 14.1 MB, once, then cached by your browser |
| Quality | Lossy, first generation |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Transparency | Dropped | The target format has nowhere to put it. |
| Extra images | Dropped | The target format has nowhere to put it. |
Worth knowing before you start:
- ImageMagick is asked for a single image, so only the first frame, page, or icon size is read
What is an ICON file?#
ICON is ImageMagick's alternate name for the ICO format, the container Windows uses for small multi-resolution images shown as application, file and shortcut icons, so a file written as ICON is the same Windows icon container as one written as ICO.
Use ICON, or the equivalent ICO, for Windows application icons, favicons and shortcut images, where the file needs to offer several sizes in one container.
Convert to PNG when a single-resolution image is needed for general use, since most software outside Windows icon contexts doesn't expect an ICO/ICON container.
What is a PJPEG file?#
PJPEG is progressive JPEG, a JPEG encoding choice rather than a different file format, where the image is built up through several increasingly detailed scans across the whole picture instead of filling in top to bottom in one pass.
Choose progressive encoding for images shown over a slow or uncertain connection, where a quick blurry preview beats a slow top-down reveal.
Convert to baseline JPEG when a downstream tool or embedded device only supports the simpler sequential scan order.
ICON to PJPEG questions people ask#
What is the difference between ICON and ICO?
There isn't one. ICON is ImageMagick's alternate name for its ICO coder, so a file written as ICON is the same Windows icon container as one written as ICO.
Why does ImageMagick have both ICO and ICON as format names?
ImageMagick registers ICON alongside ICO purely as a naming convenience, since some tools and scripts refer to Windows icon files by either name. Both write the same icon container.
What can an ICON/ICO file store?
An ICO/ICON file can store several versions of the same image at different sizes and color depths in one container, which is how Windows shows the right icon size for a desktop shortcut, a taskbar button, or a file listing.
What is PJPEG?
PJPEG is progressive JPEG, a JPEG file encoded in a handful of increasingly detailed scans instead of one pass from top to bottom. It's still a JPEG file, just encoded differently, and opens anywhere JPEG does.