Convert JPG to AVIF offline, in bulk

Why convert JPG to AVIF

Web images where every kilobyte counts and the audience uses current browsers.
Storing a large photo archive compactly.
Testing AVIF against WebP for a site before switching.

How to convert JPG to AVIF in ConvertX

1
Open Image Converter
On the Home screen tap Image Converter.
2
Select your JPG files
Tap "Select image files" and pick the JPG images (.jpg, .jpeg). On desktop you can also drag them in from Explorer or Finder.
3
Choose AVIF as the target
In the output format list choose AVIF.
4
Optional settings
Add a rename pattern (use {name} for the original file name), turn on "Keep photo details" if you want camera and location data copied into JPG, PNG or WebP output, and pick an output folder (Android default: Pictures/ConvertX).
5
Start the batch
Tap "Convert N images". The Queue opens and processes them in order; you can stop one file or the whole batch.
6
Find the results
When the batch finishes, the summary shows the files converted and the space saved. Tap View Library to browse them, or find them in the output folder.

Step-by-step with screenshots: WebP vs AVIF: which should you convert to?.

What to know before you convert

ConvertX writes AVIF but cannot read it back. Keep the JPG if you may edit the image again.
AVIF encoding is slow: expect several seconds per large photo. On Android the queue keeps going if the screen locks.
Not every app opens AVIF yet (older Windows, some editors). Check the recipient before sending.
AVIF output carries no EXIF in ConvertX.

JPG vs AVIF: what changes

	JPG	AVIF
Compression	Lossy	Lossy
Transparency	No	Yes
Animation	No	No
Keeps EXIF in ConvertX	Yes	No
ConvertX reads it	Yes	No
ConvertX writes it	Yes	Yes
Extensions	.jpg, .jpeg	.avif

JPG: The universal photo format. Small, lossy, opens everywhere, no transparency. AVIF: The newest format, smallest files, still not opened by everything. ConvertX writes it but cannot read it.

Nothing is uploaded

ConvertX converts on the device. There is no server, no account and no file size or count limit beyond your storage. Location and camera details are removed from every output unless you turn on "Keep photo details" (AVIF output never carries them in ConvertX).

Frequently asked questions

How much smaller is AVIF than JPG?

40–60 % smaller at the same visible quality is typical for photos.

Why does it take so long?

AV1 encoding does far more work per pixel than JPG. Large batches are best started and left to run.

Can I convert AVIF back to JPG with ConvertX?

No. AVIF is output-only. Keep your JPG originals.

Ready? Download ConvertX: free, with no ads, on Android and desktop.

Convert JPG to AVIF: half the size, same picture