Add your images
Choose individual files, load a whole folder at once, or drag and drop images into the queue.
Compress Images Online Free
Drag the slider to compare the original and the compressed image, tune the encoder, then batch process a whole folder without uploading anything.
Animated images are flattened.
Animated GIF, WebP and AVIF files are compressed from the first frame only; the animation is not preserved.
Choose at least one image to see the before and after comparison.
This browser cannot display that output format, so the compressed side stays blank. The downloaded file is still encoded correctly.
Drag the divider to compare, then switch to Actual size to inspect fine detail.
Compression settings
Smaller fileHigher quality
Output keeps the original size.
Original—
Compressed—
Saved—
Encoder—
Encoding uses self-hosted WebAssembly builds of MozJPEG, libwebp, libaom (AVIF), libjxl and OxiPNG from the Squoosh project by Google Chrome Labs and jSquash, both licensed under Apache-2.0. 73hi is not affiliated with or endorsed by Google.
Three simple steps
How to Compress an Image Online
Reduce image file sizes without installing software or waiting for an upload.
Compare and tune
Drag the comparison slider, pick an output format and move the quality slider until detail and size feel right.
Download the result
Save one compressed image or download every finished image together as a ZIP archive.
Format comparison
Which Output Format Should You Choose?
Every format below is encoded locally in your browser by the same WebAssembly codecs used by well-known image tools.
| Format | Typical file size | Transparency | Encoding speed | Common use |
|---|---|---|---|---|
| WebP | Small | Yes | Fast | Websites and everyday sharing |
| AVIF | Smallest | Yes | Slower | Modern browsers, hero images |
| JPEG XL | Small | Yes | Medium | Archives and future-proof delivery |
| JPEG | Medium | No | Fastest | Photos for any device |
| PNG | Larger but lossless | Yes | Fast | Screenshots, logos, graphics |
Free image compressor
See the Difference Before You Download
A comparison-first workflow that keeps your source images on your own device.
Before and after slider
Drag the handle to switch between the original and the compressed image, then zoom in to inspect fine detail.
Batch and folder loading
Queue any number of images or load an entire folder at once, then compress the whole queue with one click.
Full encoder control
Pick WebP, JPEG, AVIF, JPEG XL or PNG, set quality and effort, and optionally resize with a Lanczos3 resampler.
Private local processing
Decoding and encoding run with WebAssembly inside your browser. No image is uploaded, stored or shared.
Input compatibility
Supported Image Formats
Input support follows your browser's own decoders, so most common formats can be loaded directly.
JPG / JPEG
PNG
WebP
AVIF
GIF first frame
BMP
Other browser-supported images
Animation limit: animated GIF, WebP and AVIF inputs are compressed from the first frame only. Metadata such as EXIF is not copied to the output.
Questions and answers
Image Compressor FAQ
Is this image compressor free?
Yes. You can compress images online free with no signup, no daily limit and no watermark on the exported files.
Are my images uploaded to a server?
No. Decoding, resizing and encoding all run locally in your browser with WebAssembly and canvas. Your images are never sent to the 73hi server.
Which output formats are supported?
You can export WebP, JPEG, AVIF, JPEG XL and PNG. PNG output is lossless, so the pixels stay identical while the stored file still gets smaller.
Can I compress a whole folder at once?
Yes. Use Choose folder to load every image inside a directory, adjust the settings once, then select Compress all to process the queue in a single pass.
What quality setting should I use?
A value between 70 and 85 is a practical starting point for photos. Drag the comparison slider and zoom in to check fine detail before downloading.
Why is AVIF slower than WebP?
AVIF uses a more complex encoder that trades speed for a smaller file. Lower the encoder effort for faster results, or use WebP for large batches.
Does the compressor work on mobile?
Yes. The page adapts to phones and tablets, although very large images depend on the memory available on your device.