JPEG XL can losslessly recompress a JPG about 20% smaller with zero quality change — a genuine free size reduction rather than a trade-off. Filemorph converts JPG to JXL on iPhones running iOS 18 or later, on-device.
Most format conversions trade some quality for a smaller file. JPEG XL's lossless recompression mode is different: it can re-pack the exact same JPG data into a smaller container without discarding anything, which is close to a free size reduction for archival photo libraries.
Filemorph uses ImageIO's JPEG XL encoder to perform this conversion, which requires iOS 18 or later — the encoder is not available on earlier versions of iOS. The output is a .jxl file at roughly 15 to 20% smaller than the source JPG.
In the app: Convert → To JXL.
JPEG XL's lossless mode shrinks a JPG without losing any image data, which makes sense for photo archives where storage matters but quality cannot be compromised. Keep JPG copies for sharing until JXL support is more widespread on the apps and services you use.
Yes. Unlike web converters that upload your files to a server, Filemorph converts every file locally using Apple's frameworks. Nothing leaves your device, and it works with no internet connection. This conversion is in the free tier. Requires iOS 18+.
No, when using Filemorph's lossless JXL conversion the original JPG data is preserved exactly — only the container format changes.
Apple's JPEG XL encoder in ImageIO was introduced in iOS 18. On earlier versions of iOS, this specific conversion is not available.
Yes, it is in Filemorph's free tier, on devices running iOS 18 or later.
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