Drag & drop an image here
or
JPG, PNG, WebP, AVIF, GIF, BMP, TIFF, ICO or SVG — or paste with Ctrl+V. Compressed on your device.
Professional codecs, on your device
Guide last reviewed: 20 October 2026
Browsers have their own built-in JPG and WebP encoders, but they are tuned for speed, not size. This compressor uses the encoders that image professionals use instead — MozJPEG, Google's libwebp, libavif and the OxiPNG PNG optimiser — compiled to WebAssembly and run in a background worker on your own computer or phone. They are the same open-source codecs behind Google's Squoosh, so you get the same small files, plus a few things Squoosh doesn't do: a target file size, more input formats and batch processing.
| Encoder | Best for | Typical saving* |
|---|---|---|
| MozJPEG | Photos that must open everywhere | 60–80% |
| WebP | Websites, photos with transparency | 70–85% |
| AVIF | The smallest photos for modern browsers | 80–90% |
| OxiPNG + palette | Screenshots, logos, icons, charts | 20–80% |
*Compared with an unoptimised camera JPG or PNG export at the same dimensions; the exact figure depends on the image.
How to compress an image
- Drop an image on the page, click to browse, or paste one with Ctrl+V.
- Pick an encoder — the tool suggests one based on your image (WebP for transparency, OxiPNG for small PNG graphics, MozJPEG for photos).
- Drag the quality slider, or tick Target file size and type a limit such as 100 KB.
- Drag the divider on the preview to compare the original and the compressed version; switch to 100% to inspect fine detail.
- Optionally resize (presets for Full HD, Instagram and more) and fine-tune the advanced settings, then download.
Tips for the smallest file that still looks good
- Resize first. Halving the width and height removes three quarters of the pixels — no quality setting saves as much.
- Quality 70–80 is the sweet spot for MozJPEG and WebP photos; AVIF looks good from about 50–60. Inspect skies, skin and text at 100% zoom.
- Screenshots and logos: use OxiPNG with 64–256 colours. Text stays perfectly sharp, unlike JPG.
- Higher effort makes files a few percent smaller at the cost of encoding time — worth it for images you publish once and serve many times.
- Full colour detail (4:4:4) keeps thin red and blue lines crisp in graphics; for ordinary photos the default saves bytes with no visible change.
Frequently asked questions
Which encoder should I choose?
For photos, AVIF gives the smallest files and WebP is a close second with wider support; MozJPEG is best when the file must open everywhere (email, print shops, old software). For screenshots, logos and graphics, use OxiPNG — with palette reduction it is often 60–80% smaller while still a PNG.
How do I compress an image to a specific size, like 100 KB?
Tick Target file size, enter the size in KB and the tool searches for the highest quality that fits — useful for upload limits on job portals, government forms and marketplaces. If even the lowest quality is too big, also turn on Resize to reduce the pixel dimensions.
Is this as good as Squoosh?
It uses the same open-source codecs (MozJPEG, libwebp, libavif and OxiPNG compiled to WebAssembly), so at the same settings the files are the same size. On top of that it adds a target-file-size mode, opens TIFF, BMP, ICO and SVG, and the same encoders are available for whole folders in the Batch Image Processor.
What's the difference between resizing and compressing?
Resizing changes an image's pixel dimensions; compressing keeps the dimensions but stores the pixels more efficiently. For the biggest saving, do both: a 4000-pixel photo shown on a website at 1600 pixels wide is mostly wasted bytes.
Does PNG palette reduction lose quality?
It reduces the image to a limited set of colours (for example 64 or 256), which is invisible on most logos, icons, charts and screenshots and greatly shrinks the file. Smooth photos and gradients can show banding — keep dithering on, or use WebP or AVIF for photos instead.
Are my images uploaded?
No. Images are decoded and encoded on your own device in a background worker; only the codec program itself is downloaded the first time you use each format. You can verify this in your browser's network panel.
Does compressing an image multiple times keep degrading it?
Yes, for lossy formats (JPG, WebP, AVIF) — each re-save compounds the loss, so always compress from your original, highest-quality file. OxiPNG and lossless WebP never change a single pixel.