How to compress images online in 3 steps
Add your images
Drag and drop images onto the box above, or press Add images to pick them from your device. You can add as many files as you like at once.
Adjust the settings
Compression starts immediately at 70% quality. Open Settings to change the quality, set a maximum width or height, or convert images to WebP, JPG or PNG.
Download the result
Download each image with the button next to it, or get them all in one ZIP file. The compare button shows the original and the result side by side.
Why use this image compressor
Fully private
Compression runs inside your browser using Web Workers. Your images never leave your device and no server ever sees them, which matters for documents and personal photos.
No limits
There is no cap on the number of images or the size of a single file, no sign-up and no queue. Speed depends only on your device.
Works offline
Once the page has loaded it makes no network requests. You can disconnect and keep compressing as usual.
Faster websites
Images are usually the heaviest part of a web page. Smaller images load faster and improve Largest Contentful Paint (LCP), one of Google’s Core Web Vitals.
What is image compression?
Image compression re-encodes an image so it takes up less space, and there are two kinds. Lossless compression rebuilds exactly the same pixels when the file is opened and typically saves 10% to 40%. Lossy compression discards detail the eye barely notices and can save up to 90%, with a difference that is hard to spot in normal use.
For JPEG and WebP, the quality slider controls how much detail is discarded. PNG works differently: savings come from reducing the number of colours stored in the image’s palette, and the quality slider does not affect it. A 256-colour palette is always built with the UPNG.js library, which suits graphics, logos and screenshots and keeps transparency intact. If you need full colour accuracy, turn on Lossless PNG for a pixel-for-pixel copy of the original.
A practical tip: don’t upload a 4000-pixel-wide photo to display it at 800 pixels. Set a maximum width or height that matches your layout first; reducing dimensions usually saves more than any quality setting.
Convert image formats: PNG, JPG and WebP
The tool also converts between formats while it compresses. Open Settings and choose an Output format:
- Convert PNG to JPG: best for photos and colourful screenshots; the file often shrinks to a fraction of the original. Transparent areas become white because JPG does not support transparency.
- Convert JPG to PNG: useful when you need a lossless format to edit the image later, though the PNG is usually larger than the JPG.
- Convert images to WebP: the smallest size at the same quality, with transparency support. The best choice for website images.
Conversion happens inside your browser just like compression, so no image is ever uploaded.
Supported formats
| Format | Input | Output | How it is processed |
|---|---|---|---|
JPG / JPEG | Yes | Yes | Re-encoded at the chosen quality; EXIF data removed |
PNG | Yes | Yes | 256-colour palette via UPNG.js, or lossless when enabled |
WebP | Yes | Yes | Native WebP encoding in the browser |
GIF / SVG | No | No | Not supported by this tool |
Transparency in PNG and WebP is fully preserved. The EXIF orientation tag is applied to the image before it is removed, so photos never come out rotated.
Frequently asked questions
Are my images uploaded to a server?
No. The page reads the file from your device and processes it inside your browser with Canvas and Web Workers. Not a single byte is sent over the network; you can confirm this in the Network tab of your browser’s developer tools.
Is there a limit on image size or the number of images?
The tool sets no limit. Because processing happens on your device rather than on a shared server, the only constraint is your browser’s memory. In our tests a 12-megapixel, 27 MB PNG finished compressing in about ten seconds.
How much smaller will my images get?
It depends on the image. Photographic JPEGs usually shrink by 60% to 85% at 70% quality, and PNG graphics and logos by 50% to 90%. Images that are already heavily optimised may have little left to save; if the result would be larger than your file, the tool keeps your original instead of giving you a bigger one.
Does compression reduce image quality?
At 70% quality the difference is practically invisible on the web. Raise the slider to 85% or more for sensitive images, or turn on Lossless PNG for an exact copy of the original. The quality slider does not affect PNG files.
Does it work offline?
Yes. Once the page has loaded you don’t need a connection. Everything needed for compression is part of the page itself, and no library or font is loaded from an external server.
When should I convert images to WebP?
When the images are for a website. WebP files are smaller than JPEG and PNG at the same quality and are supported by every modern browser; choose Convert all images to WebP in Settings. Avoid it if the image will be opened in older software that doesn’t recognise the format.
Is EXIF data kept?
No. It is removed during re-encoding, including the location and the camera model, which helps privacy and trims the file slightly. The orientation tag is applied to the image before removal so it stays upright.
Is this image compressor free?
Yes. It is completely free, with no sign-up, no watermark and no daily limit.