This free image compressor makes photos and graphics smaller so pages load faster and files are easier to share on email or WhatsApp. It works entirely in your browser: your images are never uploaded to a server.
How to use the image compressor
- Add your images. Drag and drop them onto the box, or click to choose them. You can add up to 20 JPG, PNG or WebP files at once.
- Choose the output format: JPEG or WebP.
- Set the quality with the slider, from 10 to 100. Lower numbers give smaller files and softer detail.
- Optionally enter a maximum width in pixels, such as
1600. Wider images are scaled down to that width, and the height follows to keep the shape. Leave it empty to keep the original size. - Check the results. For each image you see the original size, the new size and the percentage saved.
- Download each image on its own, or all of them together as one ZIP file.
Tip: If a compressed result would be larger than the original, the tool keeps the original file instead. This can happen with images that were already well compressed.
Lossy and lossless compression
There are two ways to make an image file smaller. Lossless compression packs the same pixels more efficiently, so nothing is lost. Lossy compression throws away detail that is hard to see, which saves far more space. The quality slider controls how much a lossy encoder is allowed to throw away.
Both output formats here are lossy. JPEG has been the standard for photos for decades. WebP is a newer format that every major browser supports. According to MDN’s image format guide, lossy WebP files are on average 25–35% smaller than JPEGs of similar visual quality.
| Format | Compression | Transparency | Good for |
|---|---|---|---|
| JPEG | Lossy | No | Photos; files that must open everywhere |
| PNG | Lossless | Yes | Screenshots, logos, line art |
| WebP | Lossy or lossless | Yes | Photos and graphics on websites |
Watch out: JPEG cannot store transparency. If you convert a PNG logo with a transparent background to JPEG, the transparent areas get filled with a solid colour. Choose WebP output if you need to keep them.
Which quality setting should you use?
There is no single best number, because it depends on the picture. As web.dev’s JPEG guide points out, the differences across much of the quality scale are hard to see, even side by side. A practical way to work:
- Start around 75–80 for photos and compare the result with the original at full size.
- If it still looks fine, try a lower value. If you see blocky patches or smudged edges, go higher.
- Text, screenshots and diagrams show compression damage sooner than photos. Keep these higher, or keep them as PNG.
- Compress from the original each time. Re-compressing an already compressed JPEG adds new artefacts every round.
Resize first, then compress
The biggest savings often come from the maximum width setting, not the quality slider. A phone photo can be 4,000 pixels wide, but a blog column might only show 800 pixels of it. Even allowing for high-density screens, a width of about 1,600 pixels is plenty for most web layouts. Fewer pixels means a much smaller file before any compression starts.
For a website, use this image compressor together with good HTML: set width and height on your <img> tags and lazy-load images further down the page. Our post on image optimization for the web covers these steps, and the HTML images lesson explains the tags.
Learn more
- Image Optimisation for the Web: Formats, Sizes and Lazy Loading
- HTML Images
- Core Web Vitals for Designers: LCP, INP and CLS in Plain English
- Image Resizer
- PDF Compressor
Frequently asked questions
Are my images uploaded anywhere?
No. The images are read and re-encoded by your own browser, and the downloads are created on your device. Nothing is sent to a server.
Why is one of my images not any smaller?
Some images are already compressed about as far as they can go. If the new version would be bigger than the original, the tool keeps the original, so you never end up with a larger file.
Does compressing remove photo metadata?
Usually, yes. The image is redrawn and saved again by the browser, and camera details such as EXIF data (which can include GPS location) are normally not copied into the new file. Check the result if you rely on that data.
Should I pick JPEG or WebP?
For a website, WebP usually gives a smaller file at the same visible quality, and it keeps transparency. Pick JPEG when the file must open in older software or be uploaded to a form that only accepts JPG.