Image formats, explained plainly
What each format is for, where it fails, and how ConvertX handles it. Green means the app both reads and writes it; AVIF is write-only, HEIC and GIF are read-only.
- JPGRead & write
The universal photo format. Small, lossy, opens everywhere, no transparency.
- PNGRead & write
Lossless with transparency. Perfect for graphics, wasteful for photos.
- WebPRead & write
Google's web format: about a third smaller than JPG, with optional transparency and lossless mode.
- AVIFWrite only
The newest format, smallest files, still not opened by everything. ConvertX writes it but cannot read it.
Output only: ConvertX writes AVIF but cannot open it.
- HEICRead only
Apple's default photo format since 2017. Half the size of JPG, opens in few places outside Apple.
Input on Android 9 or later only (system decoder). Not on desktop.
- BMPRead & write
Windows' raw bitmap: no compression, huge files, trivial to decode.
- TIFFRead & write
The professional container for scans and print masters. Flexible, lossless, large.
- GIFRead only
The 1987 format that refuses to die. 256 colours, animation, big files.
Input only. ConvertX reads GIF (animation preserved when converting to WebP) but does not write new GIFs.