The AVIF encoder loads when you add your first image.
Images are compressed on your device. Nothing is uploaded.
How to compress an AVIF image
Drop one or more AVIF files into the tool. Each one is compressed right away with the quality setting on the left, and the preview shows the original and compressed versions side by side. Drag the divider to compare them, or switch to 100% to check fine detail. When it looks right, download the file, or grab everything at once as a ZIP.
Changing a setting recompresses your images automatically. The image you're looking at goes first, then the rest of the batch.
You can also drop in JPG, PNG or WEBP files. They come out as AVIF, which is often the quickest way to shrink a big photo for a website.
What quality setting should you use?
AVIF holds up well at lower quality numbers than JPG does, so don't judge it by JPG habits. For photos on a website, 45 to 55 usually looks clean while cutting the file a lot. Drop to the 30s for thumbnails and backgrounds. Go to 70 or higher for product shots, artwork or anything with small text.
Resizing usually saves more than lowering quality. A 4000 px wide photo shown in a 1200 px column is mostly wasted pixels, so pick a max size before you start lowering the quality slider.
The Effort setting trades time for size. Smaller, slower takes longer to encode but squeezes out a few extra percent at the same quality.
Why the file sometimes gets bigger
If an AVIF was already saved at a low quality, compressing it again at a higher setting can make it larger, because the encoder is preserving the artifacts as detail. Lower the quality below what the original used, or resize the image. The tool flags any file that grows so you don't download it by mistake.
AVIF vs WebP vs JPG
| AVIF | WebP | JPG | |
|---|---|---|---|
| Typical size at similar quality | Smallest | Small | Largest |
| Transparency | Yes | Yes | No |
| Encoding speed | Slowest | Fast | Fastest |
| Browser support | Chrome, Edge, Firefox, Safari 16+ | All current browsers | Everywhere |
How this tool encodes AVIF
Most browsers can display AVIF but can't save it from a canvas. This tool uses libavif, the reference AVIF encoder, compiled to WebAssembly so it runs inside your browser. It downloads once the first time you use it. Your images are decoded, resized and encoded on your device, and metadata such as EXIF and GPS location is removed in the process.
If the encoder can't load (for example on a locked-down network that blocks it), the tool tells you and falls back to WebP so you still get a smaller file.
Frequently asked questions
Is it safe to compress private images here?
Yes. Your images never leave your device. Compression runs in your browser, and the page only downloads the encoder itself.
Can I compress several AVIF files at once?
Yes. Drop as many as you like. They're compressed one after another with the same settings, and Download all saves them as a single ZIP.
Does compressing remove EXIF data?
Yes. Re-encoding strips camera details, GPS location and other metadata, which also trims a few kilobytes.
What does lossless AVIF do?
Lossless keeps every pixel exactly the same. It's useful for screenshots and graphics, but for photos it often makes a much bigger file than lossy AVIF, and sometimes bigger than PNG.
Why is encoding slow on large images?
AVIF is one of the most demanding formats to encode. A 12 megapixel photo can take several seconds. Resizing first, or switching Effort to Fast, speeds it up a lot.