About this tool
Large images slow down websites, fill up inboxes and hit upload limits. This compressor reduces the file size of JPG, PNG and WebP images while letting you see exactly how much quality you are trading for each kilobyte saved.
Move the quality slider and the result updates straight away, with the original and compressed sizes side by side. For photos, a quality setting between 70 and 85 usually gives a much smaller file with little visible difference. PNG files are compressed by reducing their colour palette, which works especially well for screenshots, icons and flat graphics.
How to use it
- Drop an image onto the upload area, or click to choose one.
- Adjust the quality slider and, if you like, pick a different output format.
- Compare the before and after preview and file sizes.
- Download the compressed image.
Frequently asked questions
Are my images uploaded anywhere?
No. Compression happens inside your browser using the built-in canvas API. The image is never sent to a server — not to ImageFlock and not to anyone else.
Why is my compressed file bigger than the original?
Some images are already heavily optimised. Re-encoding them at a high quality setting can produce a larger file. If that happens, the tool tells you, and you can lower the quality, switch to WebP, or simply keep your original.
What quality setting should I use?
For photos on websites, 75–85 is a sensible starting point. For images where detail matters, such as product shots, try 85–90. Use the before/after preview to check for blurring or blocky artefacts.
Does compression remove metadata?
Yes. Because the image is redrawn and re-encoded, EXIF data such as camera details and GPS location is not carried over to the compressed file.