Convert JPEG 2000 to ICO on Mac
Select the JPEG 2000 files in Finder, press ⌥ F, choose ICO and press Return. FileFlip saves each ICO next to its original and works without an internet connection.
How to convert JPEG 2000 to ICO with FileFlip
Select the JPEG 2000 files
In Finder or on the Desktop. One file, or a whole folder with ⌘ A.
Press ⌥ F
FileFlip opens next to the selection and lists the formats it can make from JPEG 2000. Type “ICO” to jump to it.
Choose ICO and press Return
The ICO files appear next to the originals with the same names. The JPEG 2000 files stay as they are.
JPEG 2000 and ICO
JPEG 2000 is rarely supported outside specialist software. ICO is what Windows uses for icons and what browsers look for as favicon.ico.
What changes when you convert
- ICO is lossless, so the image is saved without further loss.
- ICO images are at most 256 × 256 pixels, so large pictures are scaled down.
| Property | JPEG 2000 | ICO |
|---|---|---|
| Full name | JPEG 2000 | Windows icon |
| Made by | Joint Photographic Experts Group | Microsoft |
| Compression | Lossy or lossless (wavelet) | Bitmap or PNG inside |
| Transparency | Yes | Yes |
| Best for | Archiving and professional imaging | Windows icons and website favicons |
| Opens in | Preview and professional imaging tools; most browsers and many apps don’t open it | Windows, web browsers and most image editors |
| File extension | .jp2 | .ico |
| In FileFlip | Opens and saves | Opens and saves |
Other ways on a Mac
For one file now and then you may not need FileFlip. These work with what’s already on your Mac.
Preview
Open the JPEG 2000 in Preview, choose File → Export, pick Microsoft Icon from the Format menu and click Save. If Microsoft Icon isn’t listed, hold Option while you click the Format menu. For several files, open them together, select all thumbnails in the sidebar and choose File → Export Selected Images.
Good for a few files now and then.
Terminal
The sips command converts images in place or into a new file.
sips -s format ico image.jp2 \
--out image.icoBuilt into macOS and good for scripts. Run sips --formats to see what your macOS version can read and write.
Questions about JPEG 2000 and ICO
Does converting JPEG 2000 to ICO lose quality?
ICO is lossless, so the image is saved without further loss.
Can I convert many JPEG 2000 files at once?
Yes. Select them all in Finder, press ⌥ F and choose ICO. Progress moves to the menu bar, so you can close the panel and keep working.
How big can an ICO be?
ICO images are at most 256 × 256 pixels. Use a square source image so nothing gets stretched.
Where is the ICO file saved?
Next to the original, with the same name and the .ico extension. The JPEG 2000 file isn’t changed. In Settings you can choose a different folder instead.
Can I convert ICO back to JPEG 2000?
Yes, FileFlip converts ICO to JPEG 2000 as well.
Are my files uploaded anywhere?
No. FileFlip converts files on your Mac and works with the internet turned off.
Convert a whole folder of images at once
FileFlip also handles video, audio, PDFs, documents and data files. Requires macOS 14 Sonoma or later.
Coming soon for Mac