Compress image
Shrink the file size of your JPG, PNG, WebP and AVIF images right in your browser, free and with no usage limits. Colibrí uses professional codecs —MozJPEG for JPEG, libwebp, AVIF and OxiPNG— to squeeze every file far more than the browser’s normal compression: compress photos to email them, slim down images for your website or turn them into WebP or AVIF for the smallest possible size. You can process many at once, with no size or quantity caps. Your images are never uploaded to any server: everything happens on your device, with no sign-up, no watermarks and, as a bonus, their EXIF metadata (including GPS location) is stripped.
How to compress an image
- Drag in your images or click to choose them (you can add as many as you like).
- Choose the output format: “Keep” keeps each image’s format; WebP or AVIF give the smallest size.
- Adjust the quality and, if you need it, a maximum width or height.
- Click “Compress” and check how much size each image saves.
- Download each one or all of them together in a ZIP file.
Frequently asked questions
Are my images uploaded to any server?
No. All compression happens in your browser with WebAssembly; your images never leave your device and the tool keeps working offline once loaded. It’s safe even with private photos.
How does it reduce the size so much?
It uses the same codecs as professional tools: MozJPEG for JPEG, libwebp for WebP, AOM for AVIF and OxiPNG for PNG. They compress far better than the browser’s “Save as”, especially AVIF and WebP, which at the same quality take up much less than a JPG or a PNG.
What’s the difference between WebP and AVIF?
Both are modern formats that weigh far less than JPG or PNG and keep transparency. AVIF usually gives the smallest file (ideal for websites and for saving data), but it takes a little longer to generate. WebP is slightly larger but very fast and compatible with practically every current browser.
Do I lose quality when compressing?
It depends. JPEG, WebP and AVIF are lossy: you can adjust the quality with the slider (75 is usually a great balance). PNG is optimized losslessly with OxiPNG, so the image stays identical and just lighter. If you need to shrink a PNG a lot, try turning it into WebP or AVIF.
Is it free? Any watermarks or limits?
It’s completely free, with no watermark, no sign-up and no daily usage limit. Unlike many websites that cap you at 20 images or 5 MB per file and charge to process batches, here you compress as many images as you like at any size, and nothing is uploaded to any server.
How many images can I compress at once?
As many as you like. You can drag in a whole batch, compress them with the same settings and download them one by one or all together in a ZIP. The only limit is your device’s memory, not an artificial quota.
Is transparency preserved?
Yes, in PNG, WebP and AVIF. The JPEG format does not support transparency: if you choose JPEG, transparent areas are filled with white. To keep the alpha channel, use “Keep” (on a PNG), WebP or AVIF.
Is EXIF metadata preserved?
No, and that is usually an advantage: re-encoding the image strips the EXIF metadata, including sensitive information such as the date, the camera model or the GPS location. You get a lighter image that is more private to share.
How is it different from “Convert image”?
They overlap, but this tool is built to squeeze the file size as much as possible with professional codecs (including AVIF, which the browser can’t generate on its own). If what you mainly want is to change format, “Convert and compress images” works too.
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