Choose between WebP and AVIF by comparing actual exports, not a promised percentage saving. Keep the dimensions fixed, inspect the details your audience needs, and check the destination accepts the format. AVIF can be efficient, but a smaller file is useful only if it preserves the required appearance and works in your delivery workflow.
Start with the destination, not the encoder
A browser, store upload form, email editor and desktop application can have different format requirements. MDN documents both WebP and AVIF as web image formats, including transparency support. That does not mean every application accepts them, or that every browser can create them. Browser image decoding and Canvas export are separate capabilities.
Make a fair comparison
- →Keep an untouched original and choose one target width and height.
- →Export a WebP and an AVIF using an encoder that supports each format.
- →Do not assume the same quality number means the same appearance across encoders. Adjust each export independently.
- →Inspect fine text, hair, fabric, gradients and transparent edges at full size.
- →Compare the byte sizes only after both versions meet your visual requirements.
- →Open the chosen file in the destination application, not just your local preview.
Example: a product photograph
Illustrative workflow: start from a 3000-pixel-wide photograph intended for a 900-pixel product panel. Decide whether you also need a higher-density or zoom version before resizing. Make both format candidates at the same chosen dimensions and check the product label. If one export makes the label harder to read, raise its quality before comparing sizes. There is no universal winning byte count.
When to keep a simpler workflow
Keep JPEG when a receiving system requires it. Keep a lossless source for later edits, regardless of the delivery format. For a website, responsive image dimensions and loading behavior matter alongside the format. Do not replace a correctly sized file with an oversized AVIF and assume the page must become faster.
ZipMyImages runs in your browser, so available exports depend on the browser encoder. If an AVIF export is unavailable or its actual file type does not match the requested format, use a supported WebP or JPEG export or a dedicated AVIF encoder. Renaming a file extension does not convert the image.