Advanced Image Compressor (AVIF, MozJPEG, WebP)
The same codec engines as squoosh.app, running entirely in your browser. Encode to AVIF (typically 30–50% smaller than JPEG), MozJPEG (better than the browser's built-in JPEG), WebP or an optimised PNG, with a quality slider, an effort setting, an optional resize, and a drag-to-compare before/after view. One image or a whole batch. Nothing is uploaded.
Uses the Squoosh / jSquash WebAssembly encoders — MozJPEG, WebP, AVIF and OxiPNG — the same engines as squoosh.app, running entirely in your browser. AVIF is typically 30–50% smaller than JPEG at the same quality; MozJPEG beats the browser's built-in JPEG encoder. Nothing is uploaded.
How to use it
- Pick a format — AVIF for the smallest files, MozJPEG for broad compatibility, WebP for a balance, PNG (optimised) for lossless.
- Set the quality and, if you like, a maximum dimension.
- Drop in one or more images and click Compress.
- Drag the before/after divider to check, then download (a single file or a ZIP).
FAQ
- How is this different from the other compressors?
- The others use your browser's built-in encoder (JPEG/PNG/WebP only). This one runs the Squoosh WebAssembly codecs — so it can output AVIF, and its MozJPEG and OxiPNG produce smaller files than the browser can.
- Why is AVIF slow?
- AVIF encoding is computationally heavy and runs single-threaded in the browser for compatibility. Expect a few seconds per image; set a maximum dimension for large photos to speed it up.
- Will AVIF open everywhere?
- Every current browser displays AVIF, and so do modern versions of Android, iOS, Windows and macOS. Some older apps and some chat platforms don't yet — use WebP or MozJPEG if you need maximum compatibility.
- Is anything uploaded?
- No. The codecs run as WebAssembly in your browser; the images never leave your device.
Related tools
- Bulk Image Resizer & CompressorResize, compress and convert many images at once — download them all as a ZIP.
- Add Watermark to ImageStamp a text or logo watermark on one image or a whole batch.
- Image ResizerResize a photo by pixels, percentage or cm / mm / inch — with an optional KB limit.
- Resize Image in CM, MM or InchesSet an image's real-world size in centimetres, millimetres or inches at a chosen DPI.
- Compress Image to a Target KBShrink a JPG / PNG / WebP to a specific size — 20 KB, 50 KB, 100 KB, 200 KB.
Free to use, no sign-up. Calculations run in your browser — nothing you type is sent to a server. These tools are for general information only, not professional advice. See the full tool list.