AVIF compresses better — often 20 to 30 percent smaller than WebP — but encodes more slowly and has slightly narrower support. WebP is the safer default; AVIF is worth it for large hero images.

Will transparency be preserved?

Converting to PNG, WebP or AVIF keeps the alpha channel. Converting to JPEG does not — JPEG has no transparency, so transparent areas are flattened onto a white background.

Does my browser support AVIF encoding?

Most current browsers do. If yours cannot encode AVIF, the option is disabled automatically rather than producing a broken file.

Bulk & image tools

Bulk Image Converter

Convert images between PNG, JPEG, WebP and AVIF in batches.

Convert to

Quality82%

Drop images here, or click to browseFiles never leave your device

Transparency is preserved in PNG, WebP and AVIF. AVIF usually compresses 20–30% smaller than WebP, but encodes more slowly.

About this tool

Convert a whole folder of images to a different format at once. WebP and AVIF typically cut file size substantially against JPEG at matching quality, which is usually the quickest page-speed win available on an image-heavy site.

How to use it

Drop in the images you want to convert.
Pick the output format and quality.
Download the converted set as a zip.

WebP, AVIF or JPEG

WebP is the default worth picking. Roughly 25–35% smaller than JPEG at matching visual quality, supported by every current browser, and it keeps transparency and animation.

AVIF compresses harder still — often 20–30% below WebP — and handles gradients and flat colour particularly well, avoiding the banding JPEG produces in skies. The costs are real: encoding is markedly slower, and support, while now broad, is younger.

JPEG remains the maximum-compatibility option. No transparency, no animation, but it opens everywhere including old software and print workflows.

PNG is lossless. Larger for photographs, but the right answer for screenshots, logos, line art and anything needing a hard alpha edge.

A practical approach is to serve modern formats with a fallback, letting the browser choose:

<picture>
  <source srcset="hero.avif" type="image/avif">
  <source srcset="hero.webp" type="image/webp">
  <img src="hero.jpg" alt="...">
</picture>

The silent PNG fallback

canvas.toBlob() has a trap worth knowing about if you ever build something like this yourself.

Ask for a format the browser cannot encode and it does not throw an error. It silently produces a PNG instead. You get a file named photo.avif that is actually a PNG, is larger than the JPEG you started with, and fails to display anywhere expecting AVIF.

This tool probes support on load by encoding a 1×1 canvas and checking the returned MIME type matches what was requested. Unsupported formats are disabled in the dropdown rather than producing mislabelled files.

Converting to JPEG flattens transparency. JPEG has no alpha channel, so transparent areas are composited onto white. If you need transparency, the target must be PNG, WebP or AVIF.

Converting between lossy formats compounds loss. JPEG to WebP decodes the JPEG — artefacts included — and re-encodes them. Always convert from the highest-quality original you have, not from an already-compressed copy.

Frequently asked questions

WebP or AVIF?: AVIF compresses better — often 20 to 30 percent smaller than WebP — but encodes more slowly and has slightly narrower support. WebP is the safer default; AVIF is worth it for large hero images.
Will transparency be preserved?: Converting to PNG, WebP or AVIF keeps the alpha channel. Converting to JPEG does not — JPEG has no transparency, so transparent areas are flattened onto a white background.
Does my browser support AVIF encoding?: Most current browsers do. If yours cannot encode AVIF, the option is disabled automatically rather than producing a broken file.