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ICON to JXL Converter

FileFlip converts ICON to JXL 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.

Convert ICON to

How do I convert an ICON file to JXL?#

  1. 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.
  2. Leave the target set to JXL 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.
  3. Save the JXL file. Your browser writes it straight to your downloads folder, because there was never a server holding it.

Does converting ICON to JXL lose quality?#

It depends on what is inside the file. ICON is a container rather than a codec, so whether the JXL conversion copies the streams across untouched or re-encodes them is decided by the codecs that particular file happens to use.

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 JXL actually does to the file#

Converting ICON to JXL runs on ImageMagick, downloads 14.1 MB of WebAssembly the first time and nothing after that, re-encodes or copies through depending on the codecs in the file, keeps transparency, and drops extra images.

EngineImageMagick
Conversion pathOne step: ICON → JXL
Downloaded to your browser14.1 MB, once, then cached by your browser
QualityDecided by the codecs inside the file
You get backOne file
Where it runsIn a background worker, so the page stays responsive

What survives the conversion

What is in the fileThis conversionWhy
TransparencyKeptCarried through into the converted file.
Extra imagesDroppedThe 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 JXL file?#

A JXL file stores an image under the JPEG XL coding system, a format built to losslessly repackage an existing JPEG into a smaller file or to encode a new photo at higher quality per byte than JPEG, WebP or AVIF.

Use JPEG XL for archiving and photo libraries where you want smaller files than JPEG without giving up the option to reconstruct the original JPEG exactly, especially once Chrome and Firefox finish rolling out default decoding.

Convert JXL to JPEG or PNG for anything going on the web today, since most browsers still require a manual flag to display JPEG XL directly.

ICON to JXL 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 a JXL file?

A JXL file is an image encoded with JPEG XL, a format from the JPEG standards committee designed either to losslessly shrink an existing JPEG or to encode new photos at better quality per byte than JPEG, WebP or AVIF. It became an ISO standard starting in 2021.